137 ideas
| 12997 | Analysis is the art of finding the middle term [Leibniz] |
| Full Idea: The art of finding intermediate terms (the 'middle term') is the art of 'analysis'. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.02) | |
| A reaction: This proposal is straight out of Aristotle's 'Posterior Analytics'. Nowadays we would say there was much more to analysis, the finding of necessary and sufficient conditions being the most obvious way of putting it. |
| 13009 | A reason is a known truth which leads to assent to some further truth [Leibniz] |
| Full Idea: A reason is a known truth whose connection with some less well-known truth leads us to give our assent to the latter. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.17) | |
| A reaction: This is plainly false, because you can have a reason for believing something, but still not give your assent to it, presumably because of counter-reasons. And a false belief could also be a reason, even to believe a truth. Tut tut. |
| 12963 | Opposing reason is opposing truth, since reason is a chain of truths [Leibniz] |
| Full Idea: To speak against reason is to speak against truth, for reason is a chain of truths. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: Truth has a talismanic quality here (which it didn't always have). This is a lovely slogan for defenders of the Enlightenment. It forces modern critics of the Enlightenment (Adorno etc) to launch an attack on truth, which is a doomed line. |
| 19360 | General principles, even if unconscious, are indispensable for thinking [Leibniz] |
| Full Idea: General principles enter into our thoughts, serving as their inner core and their mortar. Even if we give no thought to them, they are necessary for thought, as muscles and tendons are for walking. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01.20) | |
| A reaction: Famously, Leibniz identified sufficient reason and non-contradiction as the two foundational principles. Modern logicians seem less keen on this idea, but then they have less interest in how we actually think. |
| 192 | Only one thing can be contrary to something [Plato] |
| Full Idea: To everything that admits of a contrary there is one contrary and no more. | |
| From: Plato (Protagoras [c.380 BCE], 332c) | |
| A reaction: The sort of thing for which a modern philosopher would demand a proof (and then reject when the proof couldn't be found), where a Greek is happy to assert it as self-evident. I can't think of a counterexample. |
| 12983 | A nominal definition is of the qualities, but the real definition is of the essential inner structure [Leibniz] |
| Full Idea: The essence of gold is what constitutes it and gives it the sensible qualities which let us recognize it and which make its nominal definition; but if we could explain this structure or inner constitution we would possess the real, causal definition. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.03) | |
| A reaction: This is the view which I am championing, particularly in the role of explanation in the whole game. Explanation and understanding are the hallmarks of the discovery of a real essence. However, a falsehood may explain things well. Tricky. |
| 12982 | One essence can be expressed by several definitions [Leibniz] |
| Full Idea: Although a thing has only one essence, this can be expressed by several definitions. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.03) | |
| A reaction: See Idea 12976 and Idea 12977 for a view which seems to conflict with this. He seemed to imply that once you identify the essence, the definitions converge, with multiple definitions being symptomatic of imperfect ideas of things. |
| 12976 | If our ideas of a thing are imperfect, the thing can have several unconnected definitions [Leibniz] |
| Full Idea: The result of having an imperfect idea of something is that the same subject admits of several mutually independent definitions: we shall sometimes be unable to derive one from another, or see in advance that they must belong to a single subject. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.31) | |
| A reaction: See Idea 12975 for imperfect ideas of things. Obviously the idea is that perfect knowledge will converge on a single definition, which will pinpoint the essence of a thing, and then all explanations will flow. A nice addition to the Aristotelian view. |
| 12984 | Real definitions, unlike nominal definitions, display possibilities [Leibniz] |
| Full Idea: The real definition displays the possibility of the definiendum, and the nominal definition does not. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.03) | |
| A reaction: This, I take it, is because the real definition indicates the actual powers of the thing, and not just the superficial characteristics. Is knowledge of powers identical with knowledge of possibilities? |
| 12980 | Genus and differentia might be swapped, and 'rational animal' become 'animable rational' [Leibniz] |
| Full Idea: The genus can very often be turned into the differentia, ...so that in place of saying that man is a 'reasonable animal' we could, if language permitted, say that man is an 'animable rational', a rational substance with animal nature. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.03) | |
| A reaction: This is a very telling point which rather undermines any dogmatic approach to what Aristotle says about these sorts of definitions. I don't find this account of definitions very helpful anyway. Leibniz links it to the order of cataloguing. |
| 13000 | Truth is correspondence between mental propositions and what they are about [Leibniz] |
| Full Idea: Let us be content with looking for truth in the correspondence between the propositions which are in the mind and the things which they are about. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.05) | |
| A reaction: In an age when the nature of truth was hardly debated, and theories such as coherence and pragmatism, never mind semantic accounts, were unthought of, it is interesting to see that correspondence seems obvious to Leibniz. Correct! |
| 12992 | Logic teaches us how to order and connect our thoughts [Leibniz] |
| Full Idea: Logic teaches us how to order and connect our thoughts. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.10) | |
| A reaction: Leibniz had a higher opinion of logic than contemporaries like Locke. The question is whether logic can actually teach us better order than we could otherwise manage, or whether it just describes what most thinkers do. |
| 10056 | At bottom eternal truths are all conditional [Leibniz] |
| Full Idea: At bottom eternal truths are all conditional, saying 'granted such a thing, such another thing is'. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.11.14), quoted by Alan Musgrave - Logicism Revisited §4 | |
| A reaction: Thus showing Leibniz to have sympathy with the if-thenist view. He cites geometry as his illustration. |
| 12974 | People who can't apply names usually don't understand the thing to which it applies [Leibniz] |
| Full Idea: Someone who goes wrong in relating an idea to a name will usually go wrong about the thing he wants the name to stand for. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.29) | |
| A reaction: This seems to give tentative support to a Millian account of names, whose only content is just the thing which is named. Leibniz's observation certainly seems to be right. |
| 13002 | It is always good to reduce the number of axioms [Leibniz] |
| Full Idea: To reduce the number of axioms is always something gained. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.06) | |
| A reaction: This is rather revealing about the nature of axioms. They don't have any huge metaphysical status - in fact one might say that their status is epistemological, or even pedagogic. They enable us to get out minds round things. |
| 13008 | Geometry, unlike sensation, lets us glimpse eternal truths and their necessity [Leibniz] |
| Full Idea: What I value most in geometry, considered as a contemplative study, is its letting us glimpse the true source of eternal truths and of the way in which we can come to grasp their necessity, which is something confused sensory images cannot reveal. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.12) | |
| A reaction: This is strikingly straight out of Plato. We should not underestimate this idea, though nowadays it is with us, but with geometry replaced by mathematical logic. |
| 12956 | Only whole numbers are multitudes of units [Leibniz] |
| Full Idea: The definition of 'number' as a multitude of units is appropriate only for whole numbers. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.15) | |
| A reaction: One can also define rational numbers by making use of units, but the strategy breaks down with irrational numbers like root-2 and pi. I still say the concept of a unit is the basis of numbers. Without whole numbers, we wouldn't call the real 'numbers'. |
| 12937 | We shouldn't just accept Euclid's axioms, but try to demonstrate them [Leibniz] |
| Full Idea: Far from approving the acceptance of doubtful principles, I want to see an attempt to demonstrate even Euclid's axioms, as some of the ancients tried to do. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.02) | |
| A reaction: This is the old idea of axioms, as a bunch of basic self-evident truths, rather than the modern idea of an economical set of propositions from which to make deductions. Demonstration has to stop somewhere. |
| 12932 | The idea of being must come from our own existence [Leibniz] |
| Full Idea: I would like to know how we could have the idea of being if we did not, as beings ourselves, find being within us. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: I could envisage a creature with an entirely 'externa' mind, that just focused on environment, and took its own place in it unthinkingly for granted. I suppose he's right, though. |
| 12966 | Objects of ideas can be divided into abstract and concrete, and then further subdivided [Leibniz] |
| Full Idea: Divide terms, objects of ideas, into abstract and concrete, then the abstract into absolute and relational, the absolute into attributes and modifications, and those two into simple and composite; the concrete are substances and their substantial things. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.22) | |
| A reaction: Make your tree from this: ABSTRACT{absolute[attributes(simple)(composite)][modifications(simple)(composite)],relations}CONCRETE{[substance][substantial form]} |
| 12993 | Have five categories - substance, quantity, quality, action/passion, relation - and their combinations [Leibniz] |
| Full Idea: The scheme of categories is very useful, and it might be that all that is needed are five general headings for beings - namely substance, quantity, quality, action or passion, and relation - with any formed by composition from those. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.10) | |
| A reaction: 'Action or passion' as a single category sounds intriguing. He is very keen on active force in the world of physical objects, which presumably falls into this category. His plan sounds, initially, as good as any I have heard. |
| 12989 | Our true divisions of nature match reality, but are probably incomplete [Leibniz] |
| Full Idea: It can be said that whatever we truthfully distinguish or compare is also distinguished or made alike by nature, although nature has distinctions and comparisons which are unknown to us and which may be better than ours. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.06) | |
| A reaction: This seems to me to be correct, though it is more like the credo of the sensible realist than it is like any sort of argument. |
| 12959 | We discern active power from our minds, so mind must be involved in all active powers [Leibniz] |
| Full Idea: The clearest idea of active power comes to us from the mind. So active power occurs only in things which are analogous to minds, that is, in entelechies; for strictly matter exhibits only passive power. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: If this is meant to be a precise argument, then 'so' and 'only' are blatantly unjustified. I guess that if it isn't analogous to a mind then he won't allow it to be a TRUE active power! I say mind arises from the entelechies of the physical brain. |
| 12967 | I use the word 'entelechy' for a power, to include endeavour, as well as mere aptitude [Leibniz] |
| Full Idea: If 'power' is the source of action, it means more than aptitude or ability. It also includes endeavour. It is in order to express this sense that I appropriate the term 'entelechy' to stand for power. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.22) | |
| A reaction: An 'entelechy' is, roughly, an instantiated thing, but I like what Leibniz is fishing for here - that we will never understand the world if we think of it as passive. |
| 12965 | All occurrence in the depth of a substance is spontaneous 'action' [Leibniz] |
| Full Idea: Anything which occurs in what is strictly a substance must be a case of 'action' in the metaphysically rigorous sense of something which occurs in the substance spontaneously, arising out of its own depths. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: I love this idea, which fits in with scientific essentialism. The question is whether Leibniz has idenified the end point of all explanations. Cutting edge physics is trying to give further explanations for what seemed basic, such as mass and gravity. |
| 12999 | Substances are primary powers; their ways of being are the derivative powers [Leibniz] |
| Full Idea: Primary powers are what make up the substances themselves; derivative powers, or 'faculties' if you like, are merely 'ways of being' - and they must be derived from substances. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.03) | |
| A reaction: We might talk of 'deep' and 'surface' properties, or maybe 'powers' and 'qualities' is better. 'Primary' and 'derivative' only gives the logical relationship, but not the causal relationship. |
| 5056 | Material or immaterial substances cannot be conceived without their essential activity [Leibniz] |
| Full Idea: I maintain that substances, whether material or immaterial, cannot be conceived in their bare essence without any activity, activity being of the essence of substance in general. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref) | |
| A reaction: Thus there could be no 'tabula rasa', because that would be an inactive mental substance. This strikes me as a nice question for modern physicists. Do they regard movement as essential, or an addition to bare particles? I'm with Leibniz. Essentialism. |
| 12969 | The active powers which are not essential to the substance are the 'real qualities' [Leibniz] |
| Full Idea: Powers which are not essential to substance, and which include not merely an aptitude but also a certain endeavour, are exactly what are or should be meant by 'real qualities'. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.23) | |
| A reaction: An important part of Leibniz's account. There are thus essential powers, in the 'depth' of the substance, and more peripheral powers, which also initiate action, and give rise to the qualities. The second must derive from the first? |
| 12941 | There cannot be power without action; the power is a disposition to act [Leibniz] |
| Full Idea: Where will one ever find in the world a faculty consisting in sheer power without performing an act? There is always a particular disposition to action, and towards one action rather than another. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: This is muddled. Leibniz defends powers in the possibilities of things, but he must then accept that some possibilities may never be realised, as with two complex chemicals which never ever come into contact with one another. |
| 190 | If asked whether justice itself is just or unjust, you would have to say that it is just [Plato] |
| Full Idea: If someone asked me 'Is justice itself just or unjust?' I should answer that it was just, wouldn't you? I agree. | |
| From: Plato (Protagoras [c.380 BCE], 330c) |
| 12990 | Real (non-logical) abstract terms are either essences or accidents [Leibniz] |
| Full Idea: Real (as opposed to logical) abstract terms, or at least those which are conceived as real, are either essences or parts of essences, or else accidents (i.e. beings added to a substance). | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.08) | |
| A reaction: Interesting to refer to accidents as 'beings'. This seems to fit abstraction by ignoring, since you can either ignore the accidents to get the essence, or ignore the essence to get the accidents. |
| 12939 | Wholly uniform things like space and numbers are mere abstractions [Leibniz] |
| Full Idea: Things which are uniform, containing no variety, are always mere abstractions: for instance, time, space, and the other entities of pure mathematics. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: I presume that being 'mere abstractions' denies them ontological status, and makes them creations of thought. If so, I like this idea a lot. |
| 12979 | The only way we can determine individuals is by keeping hold of them [Leibniz] |
| Full Idea: It is impossible for us to know individuals or to find any way of precisely determining the individuality of any thing except by keeping hold of the thing itself. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.03) | |
| A reaction: 'The tallest woman in London' seems to determine someone perfectly well, though only by cross-referencing universal concepts like 'tall'. |
| 11897 | A principle of individuation may pinpoint identity and distinctness, now and over time [Mackie,P] |
| Full Idea: One view of a principle of individuation is what is called a 'criterion of identity', determining answers to questions about identity and distinctness at a time and over time - a principle of distinction and persistence. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 8.2) | |
| A reaction: Since the term 'Prime Minister' might do this job, presumably there could be a de dicto as well as a de re version of individuation. The distinctness consists of chairing cabinet meetings, rather than being of a particular sex. |
| 11898 | Individuation may include counterfactual possibilities, as well as identity and persistence [Mackie,P] |
| Full Idea: A second view of the principle of individuation includes criteria of distinction and persistence, but also determines the counterfactual possibilities for a thing. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 8.5) | |
| A reaction: It would be a pretty comprehensive individuation which defined all the counterfactual truths about a thing, as well as its actual truths. This is where powers come in. We need to know a thing's powers, but not how they cash out counterfactually. |
| 12971 | If two individuals could be indistinguishable, there could be no principle of individuation [Leibniz] |
| Full Idea: If two individuals were perfectly similar and equal and, in short, indistinguishable in themselves, there would be no principle of individuation. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27) | |
| A reaction: This seems to be the main motive for Leibniz's unusual claim that there cannot be two indiscernible individuals, but it looks suspiciously like an a priori claim made about what should be an a posteriori discovery. Are electrons distinguishable? |
| 13098 | We use things to distinguish places and times, not vice versa [Leibniz] |
| Full Idea: It is by means of things that we must distinguish one time and place from another, rather than vice versa. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27) | |
| A reaction: This rests on Leibniz's relative view of space (as opposed to Newton's absolute view). If you need to re-identify a thing to individuate it, re-identifying the exact place or time seems impossible, but it is usually manageable with thing. |
| 13075 | No two things are quite the same, so there must be an internal principle of distinction [Leibniz] |
| Full Idea: In addition to the difference of time or of place there must always be an internal principle of distinction: although there can be many things of the same kind, it is still the case that none of them are ever exactly alike. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27) | |
| A reaction: This rests on Leibniz's unusual view that all things (even electrons) are qualitatively distinct. Personally I disagree with that, but agree with the idea. Things have time and place because they have identity, not the other way around. |
| 11883 | A haecceity is the essential, simple, unanalysable property of being-this-thing [Mackie,P] |
| Full Idea: Socrates can be assigned a haecceity: an essential property of 'being Socrates' which (unlike the property of 'being identical with Socrates') may be regarded as what 'makes' its possessor Socrates in a non-trivial sense, but is simple and unanalysable. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 2.2) | |
| A reaction: I don't accept that there is any such property as 'being Socrates' (or even 'being identical with Socrates'), except as empty locutions or logical devices. A haecceity seems to be the 'ultimate subject of predication', with no predicates of its own. |
| 12953 | Fluidity is basic, and we divide into bodies according to our needs [Leibniz] |
| Full Idea: Fluidity is the fundamental condition, and the division into bodies is carried out - there being no obstacle to it - according to our need. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.13) | |
| A reaction: Leibniz is referring to what he usually calls 'aggregates', like piles of bricks, which are things lacking a unifying substance. There may be no true substances, in which fluidity is the order of the day. |
| 12943 | Individuality is in the bond substance gives between past and future [Leibniz] |
| Full Idea: Within each substance there is a perfect bond between the future and the past, which is what creates the identity of the individual. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: I'm not quite sure if this means anything, but the idea that a bond across time is a necessity for intrinsic identity is interesting. The 'bond' would, I take it, have to be a causal one. |
| 11855 | Substances cannot be bare, but have activity as their essence [Leibniz] |
| Full Idea: I maintain that substances (material or immaterial) cannot be conceived in their bare essence devoid of activity; that activity is of the essence of substance in general | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref 65) | |
| A reaction: Leibniz liked the idea that God was the source of this activity, but this remark makes Leibniz a direct ancestor of modern scientific essentialism. |
| 12970 | We can imagine two bodies interpenetrating, as two rays of light seem to [Leibniz] |
| Full Idea: We find that two shadows or two rays of light interpenetrate, and we could devise an imaginary world where bodies did the same. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27) | |
| A reaction: I suspect this is a case of being able to imagine something when you don't fully understand it (like a bonfire on the Moon), but when you fully understand the modern physics of it, you see the necessity of separation between objects. |
| 12986 | The essence of baldness is vague and imperfect [Leibniz] |
| Full Idea: There are vague and imperfect essences, as in the question of how few hairs a man can have without being bald. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.05) | |
| A reaction: This example is much discussed in contemporary debate, but I now learn that it has a venerable history. The surprise here is the word 'essences', because I had taken Leibnizian essences to be 'perfect ideas', and hence precise. |
| 12968 | A 'substratum' is just a metaphor for whatever supports several predicates [Leibniz] |
| Full Idea: From the beginning we conceive several predicates in a single subject, and that is all there is to these metaphorical words 'support' and 'substratum'. So I do not see why it is made out to involve a problem. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.23) | |
| A reaction: The question is whether the substratum is 'bare' if you remove all the predicates, and clearly Leibniz believes you are left with true essential substance (although the removal process is presumably only possible in thought, thanks to God). |
| 11889 | Essentialism must avoid both reduplication of essences, and multiple occupancy by essences [Mackie,P] |
| Full Idea: The argument for unshareable properties (the Reduplication Argument) suggests the danger of reduplication of Berkeley; the argument for incompatible properties (Multiple Occupancy) says Berkeley and Hume could be in the same possible object. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 2.8) | |
| A reaction: These are her arguments in favour of essential properties being necessarily incompatible between objects. Whatever the answer, it must allow essences for indistinguishables like electrons. 'Incompatible' points towards a haecceity. |
| 12931 | Particular truths are just instances of general truths [Leibniz] |
| Full Idea: The reasons for particular truths rest wholly on the more general ones of which they are mere instances. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: Clearly particulars have their own distinctive truth, but the Leibniz case seems to be that a particular is a unique intersection for an array of general truths - and nothing else. Audrey Hepburn's smile has no generalities to it. |
| 12811 | We can't know individuals, or determine their exact individuality [Leibniz] |
| Full Idea: It is impossible for us to have knowledge of individuals and to find the means of determining exactly the individuality of everything. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.3) | |
| A reaction: Aristotle was clearly also tempted by this doubt (since universals are involved), though individuals are what he wanted to understand. I think they are wrong. Leibniz gives the bizarre reason that we can't know individuals as they each contain infinity. |
| 11877 | An individual essence is the properties the object could not exist without [Mackie,P] |
| Full Idea: By essentialism about individuals I simply mean the view that individual things have essential properties, where an essential property of an object is a property that the object could not have existed without. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 1.1) | |
| A reaction: This presumably means I could exist without a large part of my reason and consciousness, but could not exist without one of my heart valves. This seems to miss the real point of essence. I couldn't exist without oxygen - not one of my properties. |
| 11882 | No other object can possibly have the same individual essence as some object [Mackie,P] |
| Full Idea: Individual essences are essential properties that are unique to them alone. ...If a set of properties is an individual essence of A, then A has the properties essentially, and no other actual or possible object actually or possibly has them. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 2.1/2) | |
| A reaction: I'm unconvinced about this. Tigers have an essence, but individual tigers have individual essences over and above their tigerish qualities, yet the perfect identity of two tigers still seems to be possible. |
| 11886 | There are problems both with individual essences and without them [Mackie,P] |
| Full Idea: If all objects had individual essences, there would be no numerical difference without an essential difference. But if there aren't individual essences, there could be two things sharing all essential properties, differing only in accidental properties. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 2.5) | |
| A reaction: Depends how you define individual essence. Why can't two electrons have the same individual essence. To postulate a 'kind essence' which bestows the properties on each electron is to get things the wrong way round. |
| 12981 | Essence is just the possibility of a thing [Leibniz] |
| Full Idea: Essence is fundamentally nothing but the possibility of the thing under consideration. Something which is thought possible is expressed by a definition. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.03) | |
| A reaction: It is unclear whether he means 'possible modes of existence' or 'possible actions of the thing'. Leibniz sees more clearly than Aristotle that essences extend beyond the actual thing, because Leibniz is more aware of the active powers. |
| 11909 | Unlike Hesperus=Phosophorus, water=H2O needs further premisses before it is necessary [Mackie,P] |
| Full Idea: There is a disanalogy between 'necessarily water=H2O' and 'necessarily Hesperus=Phosphorus'. The second just needs the necessity of identity, but the first needs 'x is a water sample' and 'x is an H2O' sample to coincide in all possible worlds. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 10.1.) | |
| A reaction: This comment is mainly aimed at Kripke, who bases his essentialism on identities, rather than at Putnam. |
| 11899 | Why are any sortals essential, and why are only some of them essential? [Mackie,P] |
| Full Idea: Accounts of sortal essentialism do not give a satisfactory explanation of why any sortals should be essential sortals, or a satisfactory account of why some sortals should be essential while others are not. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 8.6) | |
| A reaction: A theory is not wrong, just because it cannot give a 'satisfactory explanation' of every aspect of the subject. We might, though, ask why the theory isn't doing well in this area. |
| 5057 | If you fully understand a subject and its qualities, you see how the second derive from the first [Leibniz] |
| Full Idea: Every time we find some quality in a subject, we ought to think that, if we understood the nature of this subject and of this quality, we should conceive how this quality could result from it. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref) | |
| A reaction: Thus (in Kripke's analogy) God cannot make 'subjects' on Thursday and then add 'qualities' on Friday. Add the point that all subjects are physical, and I say you have the whole story. The physical entails the mental. The laws result from the qualities. |
| 11906 | The Kripke and Putnam view of kinds makes them explanatorily basic, but has modal implications [Mackie,P] |
| Full Idea: Kripke and Putnam chose for their typical essence of kinds, sets of properties that could be thought of as explanatorily basic. ..But the modal implications of their views go well beyond this. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 10.1) | |
| A reaction: Cf. Idea 11905. The modal implications are that the explanatory essence is also necessary to the identity of the thing under discussion, such as H2O. So do basic explanations carry across into all possible worlds? |
| 12987 | For some sorts, a member of it is necessarily a member [Leibniz] |
| Full Idea: There are sorts or species such that if an individual has ever been of such a sort or species it cannot (naturally, at least) stop being of it. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.06) | |
| A reaction: Note the thoughtful 'naturally, at least', which blocks genetic engineering. But natural selection is genetic engineering. Crucially, Leibniz is not attributing this to all sorts or species, and allows exceptions. |
| 12884 | The same whole ceases to exist if a part is lost [Leibniz] |
| Full Idea: We cannot say - with complete fidelity to the truth of things - that the same whole continues to exist if a part of it is lost. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27.11) | |
| A reaction: This is the reference Simons 1987:319 gives when he claims that Leibniz accepts mereological essentialism. I think this is mereological necessity of identity, but not what I call 'essentialism'. That has to distinguish essential from non-essential. |
| 12975 | We have a distinct idea of gold, to define it, but not a perfect idea, to understand it [Leibniz] |
| Full Idea: That gold is a metal which resists cupellation and is insoluble in aquafortis is a distinct idea, for it gives us the criteria or definition of 'gold'. But it is not a perfect idea, because we know too little about cupellation and actions of aquafortis. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.31) | |
| A reaction: This connects the 'perfect idea' of something with knowing its active substance, and hence its essence. See Idea 12976 for the connection between perfect ideas and definitions. |
| 12805 | If two people apply a single term to different resemblances, they refer to two different things [Leibniz] |
| Full Idea: If one person applies the name 'avarice' to one resemblance, and some one else to another, there will be two different species designated by the same name. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 6.6.292), quoted by Nicholas Jolley - Leibniz and Locke on Essences p.199 | |
| A reaction: Part of Leibniz's sustained attack on Locke's nominal essences. There is clearly an uninteresting nominal essence, where a 'big brown bear' is necessarily brown, but in the interesting respects I think Leibniz is right. |
| 12806 | Locke needs many instances to show a natural kind, but why not a single instance? [Leibniz, by Jolley] |
| Full Idea: Leibniz points out that it is a concealed premise of Locke's argument that if a natural kind exists it must have many instances, but there seems no a priori objection to the idea of a species with just one member. | |
| From: report of Gottfried Leibniz (New Essays on Human Understanding [1704], 6.6.311) by Nicholas Jolley - Leibniz and Locke on Essences p.200 | |
| A reaction: I can't see this bothering Locke. Generally we formulate nominal essences by induction from bundles of ideas, but we can formulate a cautious first stab at it from one instance. If you see a new creature, is it a normal one, or a 'monster'? |
| 12972 | Bodies, like Theseus's ship, are only the same in appearance, and never strictly the same [Leibniz] |
| Full Idea: We must acknowledge that organic bodies as well as others remain 'the same' only in appearance, and not strictly speaking. It is rather like the river whose water is continually changing, or like Theseus's ship which Athenians constantly repaired. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27) | |
| A reaction: This is Leibniz's standard view, that something only remains the same if it has a unifying substance, and so a collection of planks is just an aggregate, and doesn't have any identity to begin with. |
| 11894 | Origin is not a necessity, it is just 'tenacious'; we keep it fixed in counterfactual discussions [Mackie,P] |
| Full Idea: I suggest 'tenacity of origin' rather than 'necessity of origin'. ..The most that we need is that Caesar's having something similar to his actual origin in certain respects (e.g. his actual parents) is normally kept fixed in counterfactual speculation. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 6.9) | |
| A reaction: I find necessity or essentially of origin very unconvincing, so I rather like this. Origin is just a particularly stable way to establish our reference to something. An elusive spy may have little more than date and place of birth to fix them. |
| 5055 | No two things are totally identical [Leibniz] |
| Full Idea: By virtue of insensible variations, two individual things can never be perfectly alike. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref) | |
| A reaction: This sounds a bit like the 'discernibility of non-identicals', except that he says that the differences may not be 'sensible'. He has to be talking of physical things, since I presume that, say, the symmetry of two circles is perfectly identical. |
| 12978 | A perfect idea of an object shows that the object is possible [Leibniz] |
| Full Idea: One mark of a perfect idea is that it shows conclusively that the object is possible. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.31) | |
| A reaction: Subtle but nice. My favourite example would be that the perfect idea of a bonfire on the Moon shows that it is not possible. Essence reveals necessity, as Aristotle and Kit Fine claim. A perfect idea has a single definition. |
| 17079 | Proofs of necessity come from the understanding, where they have their source [Leibniz] |
| Full Idea: The fundamental proof of necessary truths comes from the understanding alone, and other truths come from experience or from observations of the senses. Our mind is capable of knowing truths of both sorts, but it is the source of the former. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: Interesting because it not only spells out that necessary truths are known a priori, but also explicitly says that the understanding is the 'source' of the truths, or at least the source of their proofs. He also says possibilities derive from essences. |
| 11887 | Transworld identity without individual essences leads to 'bare identities' [Mackie,P] |
| Full Idea: Transworld identity without individual essences leads to 'bare identities'. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 2.7) | |
| A reaction: [She gives an argument for this, based on Forbes] I certainly favour the notion of individual essences over the notion of bare identities. We must distinguish identity in reality from identity in concept. Identities are points in conceptual space. |
| 11890 | De re modality without bare identities or individual essence needs counterparts [Mackie,P] |
| Full Idea: Anyone who wishes to avoid both bare identities and individual essences, without abandoning de re modality entirely, must adopt counterpart theory. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 4.1) | |
| A reaction: This at least means that Lewis's proposal has an important place in the discussion, forcing us to think more clearly about the identities involved when we talk of possibilities. Mackie herself votes for bare indentities. |
| 11892 | Things may only be counterparts under some particular relation [Mackie,P] |
| Full Idea: A may be a counterpart of B according to one counterpart relation (similarity of origin, say), but not according to another (similarity of later history). | |
| From: Penelope Mackie (How Things Might Have Been [2006], 5.3) | |
| A reaction: Hm. Would two very diverse things have to be counterparts because they were kept in the same cupboard in different worlds? Can the counterpart relationship diverge or converge over time? Yes, I presume. |
| 11893 | Possibilities for Caesar must be based on some phase of the real Caesar [Mackie,P] |
| Full Idea: I take the 'overlap requirement' for Julius Caesar to be that, when considering how he might have been different, you have to take him as he actually was at some time in his existence, and consider possibilities consistent with that. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 6.5) | |
| A reaction: This is quite a large claim (larger than Mackie thinks?), as it seems equally applicable to properties, states of affairs and propositions, as well as to individuals. Possibility that has no contact at all with actuality is beyond our comprehension. |
| 11884 | The theory of 'haecceitism' does not need commitment to individual haecceities [Mackie,P] |
| Full Idea: The theory that things have 'haecceities' must be sharply distinguished from the theory referred to as 'haecceitism', which says there may be differences in transworld identities that do not supervene on qualitative differences. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 2.2 n7) | |
| A reaction: She says later [p,43 n] that it is possible to be a haecceitist without believing in individual haecceities, if (say) the transworld identities had no basis at all. Note that if 'thisness' is 'haecceity', then 'whatness' is 'quiddity'. |
| 12960 | We understand things when they are distinct, and we can derive necessities from them [Leibniz] |
| Full Idea: We understand the things of which we are aware only when we have distinct ideas of them accompanied by the power to reflect and to derive necessary truths from those ideas. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: A rather startling way of putting it, but we also say that good understanding brings the power to predict. What must you understand in order to predict? What has to happen next! |
| 12998 | Understanding grasps the agreements and disagreements of ideas [Leibniz] |
| Full Idea: Ordinarily, when ideas are thoroughly understood, their agreements and disagreements are apparent. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.02) | |
| A reaction: In other words, there is a holistic aspect of understanding, which makes us ask how understanding ever gets off the ground. Is it not possible to understand a single idea in isolation? |
| 20185 | The most important things in life are wisdom and knowledge [Plato] |
| Full Idea: It would be shameful indeed to say that wisdom and knowledge are anything but the most powerful forces in human activity. | |
| From: Plato (Protagoras [c.380 BCE], 352d) | |
| A reaction: He lumps wisdom and knowledge together, and I think we can take 'knowledge' to mean something like understanding, because obviously mere atomistic propositional knowledge can be utterly trivial. |
| 20184 | The only real evil is loss of knowledge [Plato] |
| Full Idea: The only real kind of faring ill is the loss of knowledge. | |
| From: Plato (Protagoras [c.380 BCE], 345b) | |
| A reaction: This must crucially involve the intellectualist view (of Socrates) that virtuos behaviour results from knowledge, and moral wickedness is the result of ignorance. It is hard to see how forgetting a phone number is evil. |
| 13006 | Certainty is where practical doubt is insane, or at least blameworthy [Leibniz] |
| Full Idea: Certainty might be knowledge of a truth such that to doubt it in a practical way would be insane; and sometimes it is taken more broadly, to cover cases where doubt would be very blameworthy. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.11) | |
| A reaction: The normative aspect of the second half of this touches on a trend in recent epistemology. You have rights to believe, and duties to believe, and virtues for the justifying process. I prefer more neutral, value-free epistemology. |
| 12996 | I know more than I think, since I know I think A then B then C [Leibniz] |
| Full Idea: Not only is it immediately evident to me that I think, but it is just as evident that I think various thoughts: at one time I think about A and at another about B and so on. Thus the Cartesian principle is sound, but it is not the only one of its kind. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.02) | |
| A reaction: I don't suppose that Descartes would object to this, but he was aware that there didn't seem to be any actual introspective experience that united the various thoughts into a single thinker. Only logical connections between the thoughts does that. |
| 13003 | The Cogito doesn't prove existence, because 'I am thinking' already includes 'I am' [Leibniz] |
| Full Idea: To say 'I think therefore I am' is not really to prove existence from thought, since 'to think' and 'to be thinking' are one and the same, and to say 'I am thinking' [je suis pensant] is already to say 'I am' [je suis]. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.07) | |
| A reaction: This is the objection which was offered by A.J. Ayer, and I take it to the one of the two principle objections to the Cogito (i.e. that it may be a tautology), along with the objection about the assumption of the continuity of the same thinker. |
| 21253 | Descartes needs to demonstrate how other people can attain his clear and distinct conceptions [Leibniz] |
| Full Idea: It is not sufficient for Descartes to claim that he perceives something in himself clearly and distinctly, for this is to not complete the demonstration, unless he shows the method through which others can attain the same experience. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], App X) | |
| A reaction: For the simplest rational insight this seems a rather tough requirement. If you say A>B, and B>C, so A>C, then once you have grasped the concept of 'greater than' I'm not sure there is a further possible demonstration. |
| 12933 | Arithmetic and geometry are implicitly innate, awaiting revelation [Leibniz] |
| Full Idea: I would name the propositions of arithmetic and geometry as innate. ...The actual knowledge of them is not innate. What is innate is what might be called the implicit knowledge of them, as the veins of marble outline a shape for the sculptor. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: This seems to walk straight into the empiricist guns. The marble example shows the problem, because the 'veins' will hardly outline David in the block. Locke's challenge is to show that merely 'implicit' ideas have demonstrable reality. |
| 12991 | Children learn language fast, with little instruction and few definitions [Leibniz] |
| Full Idea: I have sometimes been amazed that children can learn languages so early, ...considering how little trouble is taken to instruct children in their native tongue, and how little thought adults give to getting sharp definitions. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.10) | |
| A reaction: A striking anticipation of the key observation on which Chomsky built his theories, from a philosopher who was equally concerned to defend innate ideas and innate knowledge. |
| 12929 | All of our thoughts come from within the soul, and not from the senses [Leibniz] |
| Full Idea: I always accepted the innate idea of God, but my new system says all the thoughts and actions of the soul come from its own depths and could not be given to it by the senses. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: It is hard to adjudicate on this one. The counterexamples would be associations. I see a face in the crowd and think of my friend. But Leibniz could be right even about that. Who cares? Externalism is designed to bypass this problem. |
| 12940 | What is left of the 'blank page' if you remove the ideas? [Leibniz] |
| Full Idea: Those who hold forth about the 'blank page' cannot say what is left of it once the ideas have been taken away. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: This is a decisive criticism of the total tabula rasa idea, but empiricists responded by developing associationism - that what remains is principles of association for incoming experience. Brain mechanisms, we might say. |
| 19358 | Colour and pain must express the nature of their stimuli, without exact resemblance [Leibniz] |
| Full Idea: Ideas such as those of colour and pain are not arbitrary. ...That is not God's way ...I would say there is a resemblance of a kind, not a perfect one, but a resemblance in which one thing expresses another through some orderly relationship between them. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.08) | |
| A reaction: The main point of Locke's idea of 'secondary' qualities is that (unlike the 'primary' ones) they bear no resemblance to their stimuli. It's not much of an argument from Leibniz, to say that is not God's way, but he has a vast system to support his claim. |
| 12948 | A pain doesn't resemble the movement of a pin, but it resembles the bodily movement pins cause [Leibniz] |
| Full Idea: It is true that pain does not resemble the movement of a pin; but it might thoroughly resemble the motions which the pin causes in our body, and it might resemble them in the soul; and I have not the least doubt that it does. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.08) | |
| A reaction: He may not have the least doubt, but the rest of us do, I should think. Try as I will, I cannot see any resemblance between pain and a motion. What feeling does a pendulum resemble? |
| 13005 | Truth arises among sensations from grounding reasons and from regularities [Leibniz] |
| Full Idea: The truth of sensible things is established by the links amongst them; these depend upon intellectual truths, grounded in reason, and upon observations of regularities among sensible things themselves, even when the reasons are not apparent. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.11) | |
| A reaction: It's not clear why regularities would establish truths, given that most hallucinations have regularities in them. I'm thinking that Leibniz is not sufficiently rationalist here, and that it is the rational coherence of experience which validates it. |
| 4302 | You may experience a universal truth, but only reason can tell you that it is always true [Leibniz] |
| Full Idea: However often one experiences instances of a universal truth, one could never know inductively that it would always hold unless one knew through reason that it was necessary. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: The problem, though, is that as soon as we go beyond experience we are not very reliable, and are liable to arrogance, error and lack of imagination. |
| 12947 | We only believe in sensible things when reason helps the senses [Leibniz] |
| Full Idea: The senses could not convince us of the existence of sensible things without help from reason. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.07) | |
| A reaction: This nicely pinpoints the big difficulty which keeps besetting orthodox empiricism. I've been educated as an empiricist, but I prefer Leibniz to Berkeley or Hume, and even to the more sensible Locke. |
| 12930 | The senses are confused, and necessities come from distinct intellectual ideas [Leibniz] |
| Full Idea: Intellectual ideas, from which necessary truths arise, do not come from the senses. ...The ideas that come from the senses are confused; and so too, at least in part, are the truths which depend on them, whereas intellectual ideas are distinct. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.01) | |
| A reaction: One might compare Descartes' example of the chiliagon, which is only grasped clearly by the intellect. However, the problem of vagueness seems to intrude as much into intellectual ideas as it does into the senses. He was a mathematician... |
| 13001 | Our sensation of green is a confused idea, like objects blurred by movement [Leibniz] |
| Full Idea: The sensory idea of green (made of blue and yellow) is a confused idea, like the swift rotation of a cog-wheel which makes us perceive an artificial transparency, and we are not able to discern the cause, the idea of the teeth on the wheel. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.06) | |
| A reaction: This is one of Leibniz's less well-known objections to empiricism. He always says that intellectual ideas are capable of a clarity which is never found in sensory experience. |
| 12949 | Light takes time to reach us, so objects we see may now not exist [Leibniz] |
| Full Idea: Since rays of light need time - however little - to reach us, it is possible that the object should be destroyed during the interval and no longer exist when the light reaches the eye. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.09) | |
| A reaction: This is the well know 'time lag' argument. Leibniz is no sceptic, but he can hardly fail to accept the truth of this problem. It seems self-evident that stars we observe may no longer exist, although special relativity confuses that issue. |
| 5053 | The instances confirming a general truth are never enough to establish its necessity [Leibniz] |
| Full Idea: All the instances which confirm a general truth, however numerous they may be, are not sufficient to establish the universal necessity of this same truth. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref) | |
| A reaction: This is Leibniz's standardly rationalist view of induction. We can either say that induction is therefore inadequate, or (a better option) that there isn't much evidence for claims of necessity, and they must be treated with caution. |
| 12977 | We will only connect our various definitions of gold when we understand it more deeply [Leibniz] |
| Full Idea: We can define gold as the heaviest metal, or by assaying procedures, but only when men have penetrated more deeply into the nature of things will they be able to see why one belongs with the other. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.31) | |
| A reaction: He mentions that geometry is different, because we do have perfect ideas of things. This is part of Leibniz's optimism about the future of science, in comparison with the surprising pessimism of the empiricists. See Idea 12976 and Idea 12975. |
| 11905 | Locke's kind essences are explanatory, without being necessary to the kind [Mackie,P] |
| Full Idea: One might speak of 'Lockean real essences' of a natural kind, a set of properties that is basic in the explanation of the other properties of the kind, without commitment to the essence belonging to the kind in all possible worlds. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 10.1) | |
| A reaction: I think this may be the most promising account. The essence of a tiger explains what tigers are like, but tigers may evolve into domestic pets. Questions of individuation and of explaining seem to be quite separate. |
| 5054 | Animal thought is a shadow of reasoning, connecting sequences of images by imagination [Leibniz] |
| Full Idea: The sequences of the brutes are but a shadow of reasoning, that is to say, they are but connexions of imagination, transitions from one image to another. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref) | |
| A reaction: This account of animal thought cannot capture the fact that they are motivated by their images, and obviously make decisions based on them. Externally, there is usually an obvious reason why even an insect does something. |
| 12944 | It is a serious mistake to think that we are aware of all of our perceptions [Leibniz] |
| Full Idea: Many errors can flow from the belief that the only perceptions in the soul are the ones of which it is aware. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: What a perceptive remark, for its time! I took it that it was only modern neuroscience and psychology which had woken us up to how much non-conscious activity is central to the mind. |
| 12951 | Abstraction attends to the general, not the particular, and involves universal truths [Leibniz] |
| Full Idea: Beasts recognise whiteness, but this does not amount to abstraction, which requires attention to the general apart from the particular, and consequently involves knowledge of universal truths. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.11) | |
| A reaction: I'm not sure where 'truth' creeps into this. I might hallucinate pink elephants, and abstract the general notion of pink from them. Nevertheless, the features picked out in abstraction tend to be the shared features. |
| 191 | Everything resembles everything else up to a point [Plato] |
| Full Idea: Everything resembles everything else up to a point. | |
| From: Plato (Protagoras [c.380 BCE], 331d) |
| 19364 | Volition automatically endeavours to move towards what it sees as good (and away from bad) [Leibniz] |
| Full Idea: Volition is the effort or endeavour ('conatus') to move towards what one finds good and away from what one finds bad, the endeavour arising immediately out of one's awareness of those things. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: Modern neuroscience seems to confirm that there is a chicken-and-egg problem here. Is the moment of perception as good or bad itself an act of volition, or is it neutral? |
| 12942 | Memory doesn't make identity; a man who relearned everything would still be the same man [Leibniz] |
| Full Idea: If a man were made young again, and learned everything anew - would that make him a different man? So it is not memory that makes the very same man. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: Leibniz takes this as a foregone conclusion. If you flipped to a possible world where someone you know well, as a physical being, has been brought up entirely differently (new language, culture, ethics etc), is it really the same person? |
| 12973 | We know our own identity by psychological continuity, even if there are some gaps [Leibniz] |
| Full Idea: To discover one's own moral identity unaided, it is sufficient that between one state and a neighbouring (or just a nearby) one there be a mediating bond of consciousness, even if this has a jump or forgotten interval mixed into it. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27) | |
| A reaction: Leibniz appears to accept the psychological continuity view of personal identity (which was probably a new problem to him), even though he rightly rejects the account based purely on memory. |
| 19368 | The will determines action, by what is seen as good, but it does not necessitate it [Leibniz] |
| Full Idea: Choice, however much the will is determined to make it, should not be called absolutely and strictly necessary: a predominance of goods of which one is aware inclines without necessitating, though this is determining and never fails to have its effect. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: Something like seeing that 7+5 equals 12 makes you say '12', but it doesn't actually necessitate your saying '12'? Certain facts seem determined by nature, but not necessitated. Or not necessarily necessitated? |
| 12935 | Every feeling is the perception of a truth [Leibniz] |
| Full Idea: Every feeling is the perception of a truth. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.02) | |
| A reaction: I wouldn't say feelings ARE perceptions of truths, but I might say that every experience we have has an intellectual dimension as well as an emotional one. Our beliefs drift and solidify in just the same way that feelings do. |
| 12938 | An idea is an independent inner object, which expresses the qualities of things [Leibniz] |
| Full Idea: An idea is an immediate inner object, which expresses the nature or qualities of things, ..but since it is the object of thought it can exist before and after the thoughts. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: This sounds something like Frege's 'third realm' between mind and world (Idea 7740). Notice that Leibniz is also using the word 'object' in this context. Leibniz doesn't make the mistake of confusing concepts and images, as many did. |
| 12950 | We must distinguish images from exact defined ideas [Leibniz] |
| Full Idea: It is essential to distinguish images from exact ideas which are composed of definitions. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.09) | |
| A reaction: See Idea 12615, which is attacking Descartes and Locke, I think, but fails to register that Spinoza and Leibniz had got the notion of an 'idea' much more clearly. |
| 12945 | Thoughts correspond to sensations, but ideas are independent of thoughts [Leibniz] |
| Full Idea: I distinguish ideas from thoughts. For we always have all our pure or distinct ideas independently of the senses, but thoughts always correspond to some sensation. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.01) | |
| A reaction: Leibniz's concept of an 'idea' is quite different from the empiricist notion of them, and strikes me as being much closer to Frege's notion of a concept. On the whole I like the Leibniz account best. |
| 19357 | The idea of green seems simple, but it must be compounded of the ideas of blue and yellow [Leibniz] |
| Full Idea: It is obvious that green comes from a mixture of blue and yellow; which makes it credible that the idea of green is composed of the ideas of those two colours, although the idea of green appears to us as simple as that of blue. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.07) | |
| A reaction: This shows the use of 'idea' at that time for non-verbal mental events and concepts. Ideas are not, then, just undestood as phenomena, but can be analysed and explained more deeply. |
| 12995 | The name 'gold' means what we know of gold, and also further facts about it which only others know [Leibniz] |
| Full Idea: The name 'gold' signifies not merely what the speaker knows of gold , but also what he does not know, which may be known by someone else: an inner constitution from which flow colour and weight, and generates other properties. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.11) | |
| A reaction: [compressed] Thus in the course of defending true essences of gold (against Locke's claim that we are stuck with the nominal essence), Leibniz drifts into an externalist account of meaning. He mentions experts, as so often does Putnam. |
| 12807 | The word 'gold' means a hidden constitution known to experts, and not just its appearances [Leibniz] |
| Full Idea: The name 'gold' signifies not only what he who pronounces it knows about it, for example, something very heavy and yellow, but also what he does not know, and that another can know about it, its internal constitution from which colour and weight flow. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 6.6.354), quoted by Nicholas Jolley - Leibniz and Locke on Essences | |
| A reaction: Leibniz goes on to use the word 'expert'. This isn't just a hint of Putnam's externalism about concepts like 'water' - it is a clear spelling out of the full idea. Locke would have been astounded by 'atomic number 79', and Leibniz would be, like, 'yeah'. |
| 12946 | The idea of the will includes the understanding [Leibniz] |
| Full Idea: The idea of the will includes that of the understanding. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.06) | |
| A reaction: A nice remark, although I am not sure that I agree with it. The understanding (if we allow such talk of faculties, with which I have no problem) sometimes lags behind and sometimes forges ahead of the will. What else is weakness of the will? |
| 203 | Courage is knowing what should or shouldn't be feared [Plato] |
| Full Idea: Knowledge of what is and is not to be feared is courage. | |
| From: Plato (Protagoras [c.380 BCE], 360d) |
| 12964 | If would be absurd not to disagree with someone's taste if it was a taste for poisons [Leibniz] |
| Full Idea: If someone acquired a taste for poisons which would kill him or make him wretched, it would be absurd to say that we ought not to argue with him about his tastes. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: This seems to be a first step in any discussion of taste on which you would hope that sensible persons would agree. 'It is just a matter of taste' is definitely not the end of discussion. Aesthetic taste is important, just as values are important. |
| 12958 | Love is pleasure in the perfection, well-being or happiness of its object [Leibniz] |
| Full Idea: To love is to be disposed to take pleasure in the perfection, well-being or happiness of the object of one's love. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.20) | |
| A reaction: I suppose so, though one might love a pathetic little plant that hangs on in the corner of the garden, just for its fighting qualities. He goes on to deny that we can truly love something that is incapable of happiness. Hm. |
| 202 | No one willingly and knowingly embraces evil [Plato] |
| Full Idea: No one willingly goes to meet evil, or what he thinks is evil. | |
| From: Plato (Protagoras [c.380 BCE], 358d) | |
| A reaction: Presumably people who actively choose satanism can override this deep-seated attitude. But their adherence to evil usually seems to be rather restrained. A danger of tautology with ideas like this. |
| 12957 | The good is the virtuous, the pleasing, or the useful [Leibniz] |
| Full Idea: The good is divided into the virtuous, the pleasing, and the useful. ..The good is either pleasing or useful; and virtue itself consists of a pleasure of the mind. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.20) | |
| A reaction: I presume that the useful could be reduced to the pleasing. It strikes me as quite bizarre to define virtue as merely a pleasure of the mind. Aristotle says true virtue must also please the mind, but that is a different idea. |
| 193 | Some things are good even though they are not beneficial to men [Plato] |
| Full Idea: 'Do you mean by good those things that are beneficial to men?' 'Not only those. I call some things which are not beneficial good as well'. | |
| From: Plato (Protagoras [c.380 BCE], 333e) | |
| A reaction: Examples needed, but this would be bad news for utilitarians. Good health is not seen as beneficial if it is taken for granted. Not being deaf. |
| 12962 | Pleasure is a sense of perfection [Leibniz] |
| Full Idea: Fundamentally, pleasure is a sense of perfection, and pain a sense of imperfection. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21) | |
| A reaction: A bit odd, but I like the idea that there is an intellectual aspect to even the most visceral feelings. |
| 197 | Some pleasures are not good, and some pains are not evil [Plato] |
| Full Idea: There are some pleasures which are not good, and some pains which are not evil. | |
| From: Plato (Protagoras [c.380 BCE], 351d) | |
| A reaction: Sadism and child birth. Though Bentham (I think) says that there is nothing good about the pain, since the event would obviously be better without it. |
| 200 | People tend only to disapprove of pleasure if it leads to pain, or prevents future pleasure [Plato] |
| Full Idea: The only reason the common man disapproves of pleasures is if they lead to pain and deprive us of future pleasures. | |
| From: Plato (Protagoras [c.380 BCE], 354a) | |
| A reaction: Plato has a strong sense that some pleasures are just innately depraved and wicked. If those pleasure don't hurt anyone, it is very hard to pinpoint what is wrong with them. |
| 12934 | We can't want everyone to have more than their share, so a further standard is needed [Leibniz] |
| Full Idea: We would wish for more than our share if we had our own way; so do we also owe to others more than their share? If the rule applies only to a just will, the rule will need a standard. The rule means that to judge fairly we must adopt others' viewpoints. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.02) | |
| A reaction: The first part of this is moving towards Kant's rational overview of ethics. Leibniz is wholly right here. All ethics faces the problem that initial values are needed to get it off the ground. What's wrong with pain, or unfairness, or hatred? |
| 188 | Socrates did not believe that virtue could be taught [Plato] |
| Full Idea: Socrates: I do not believe that virtue can be taught. | |
| From: Plato (Protagoras [c.380 BCE], 320b) |
| 204 | Socrates is contradicting himself in claiming virtue can't be taught, but that it is knowledge [Plato] |
| Full Idea: Socrates is contradicting himself by saying virtue is not teachable, and yet trying to demonstrate that every virtue is knowledge. | |
| From: Plato (Protagoras [c.380 BCE], 361b) |
| 189 | If we punish wrong-doers, it shows that we believe virtue can be taught [Plato] |
| Full Idea: Athenians inflict punishment on wrong-doers, which shows that they too think it possible to impart and teach goodness. | |
| From: Plato (Protagoras [c.380 BCE], 324c) |
| 12936 | There are natural rewards and punishments, like illness after over-indulgence [Leibniz] |
| Full Idea: There can be natural rewards and punishments without a law-maker; intemperance, for instance, is punished by illness. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 1.02) | |
| A reaction: Hm. Maybe if it didn't result in illness it wouldn't be labelled as 'intemperance'. Why isn't studying philosophy all day long classed as intemperance? |
| 11907 | Maybe the identity of kinds is necessary, but instances being of that kind is not [Mackie,P] |
| Full Idea: One could be an essentialist about natural kinds (of tigers, or water) while holding that every actual instance or sample of a natural kind is only accidentally an instance or a sample of that kind. | |
| From: Penelope Mackie (How Things Might Have Been [2006], 10.2) | |
| A reaction: You wonder, then, in what the necessity of the kind consists, if it is not rooted in the instances, and presumably it could only result from a stipulative definition, and hence be conventional. |
| 11856 | Qualities should be predictable from the nature of the subject [Leibniz] |
| Full Idea: Whenever we find some quality in a subject, we ought to believe that if we understood the nature of both the subject and the quality we would conceive how the quality could arise from it. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref 66) | |
| A reaction: This is the idea that powers are prior to properties, which seems right to me. I take essence to be something like the best explanation of qualities. |
| 12994 | Gold has a real essence, unknown to us, which produces its properties [Leibniz] |
| Full Idea: The complex idea of gold includes its being something which has a real essence whose detailed constitution is unknown to us, except for the fact that such qualities as malleability depend upon it. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.10) | |
| A reaction: This is precisely the view of modern scientific essentialism. The underlying idea I take to be the conception of essence as the thing which explains the properties. |
| 12808 | Part of our idea of gold is its real essence, which is not known to us in detail [Leibniz] |
| Full Idea: It is very true that it is part of the complex idea of gold that it is a thing which has a real essence, the constitution of which is not otherwise known to us in detail. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 6.6.345), quoted by Nicholas Jolley - Leibniz and Locke on Essences p.201 | |
| A reaction: See also Idea 12807. This is the clearest possible statement of Leibniz's clear-cut scientific essentialism, here presented in opposition to Locke (thought I take the latter to be only bothered by our inability to know the hidden constitution). |
| 12985 | Maybe motion is definable as 'change of place' [Leibniz] |
| Full Idea: I believe 'motion' to be definable, and the definition which says that it is 'change of place' deserves respect. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.04) | |
| A reaction: This seems to be the 'at-at' view of motion, championed by Bertrand Russell. (At p1 at t1, at p2 at t2...). Leibniz's version only mentions space and not time, and it includes 'change', which would need definition without mentioning motion. |
| 12952 | Space is an order among actual and possible things [Leibniz] |
| Full Idea: Space is a relationship: an order, not only among existents, but also among possibles as though they existed. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.13) | |
| A reaction: The modal end to this idea is a bit puzzling. Would there be any space if there were only possibles, and nothing yet existed, as in God's mind the instant before he got to work? |
| 12955 | If there were duration without change, we could never establish its length [Leibniz] |
| Full Idea: If there were a vacuum in space, one could establish its size. But if there were a vacuum in time, i.e. a duration without change, it would be impossible to establish its length. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.15) | |
| A reaction: See Idea 4226 for Shoemaker's wonderful counterproposal to this apparently unanswerable claim. I suppose Leibniz is right, but it just might be possible to bring induction to bear on the problem. |
| 12954 | God's essence is the source of possibilities, and his will the source of existents [Leibniz] |
| Full Idea: God is the source of possibilities and of existents alike, the one by his essence and the other by his will. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.15) | |
| A reaction: Every now and then I rebel against metaphysics, and think 'how do these people know all this great things about which they make these dogmatic claims?' And this is one of those occasions. I get the idea, though... |
| 12988 | The universe contains everything possible for its perfect harmony [Leibniz] |
| Full Idea: The universe contains everything that its perfect harmony could admit. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 3.06) | |
| A reaction: This sort of Leibnizian remark leaves most modern readers, including me, totally bewildered. The claim depends entirely on the perfect nature of God. |
| 1414 | A perfection is a simple quality, which is positive and absolute, and has no limit [Leibniz] |
| Full Idea: I call every simple quality which is positive and absolute, or expresses whatever it expresses without any limits, a perfection. But a quality of this sort, because it is simple, is therefore irresolvable or indefinable. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], App X) | |
| A reaction: I don't think this definition of perfections would have occurred to anyone who wasn't planning to prove that perfections cannot be incompatible (as Leibniz is about to do). |
| 21252 | Perfections must have overlapping parts if their incompatibility is to be proved [Leibniz] |
| Full Idea: If two propositions (about perfections) are incompatible, that cannot be demonstrated without a resolution of the terms, for otherwise their nature would not enter into the ratiocination. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], App X) | |
| A reaction: If God is omnipotent and wholly free, these appear to be fully separate perfections. But it is their implications (can God decide to do otherwise, given His foreknowledge?) which lead to a problem. So this analyis of contradiction is wrong. |
| 19328 | Without the principle of sufficient reason, God's existence could not be demonstrated [Leibniz] |
| Full Idea: There is a fundamental axiom that 'nothing happens without reason', without which the existence of God and other great truths cannot be properly demonstrated. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], 2.21.13) | |
| A reaction: I'm rather drawn to the Principle of Sufficient Reason, but also to John Keats's 'negative capability'. Belief that there must be a reason in each case is not a justification for inventing a reason every time. There may be a reason for the universe.... |
| 5058 | Animals have thought and sensation, and indestructible immaterial souls [Leibniz] |
| Full Idea: I hold (against the Cartesians) that brutes also have thought, and hold that they have sensation, and souls which are, properly speaking, immaterial, and as incapable of perishing as the atoms of Democritus or Gassendi. | |
| From: Gottfried Leibniz (New Essays on Human Understanding [1704], Pref) | |
| A reaction: Insect heaven will be a bit crowded. I can never grasp why theologians would claim that souls are 'indestructible', when they are held to come into existence at a particular moment in space-time. Transmigration of souls is a much more rational belief. |