20 ideas
| 19342 | Reason avoids multiplying hypotheses or principles [Leibniz] |
| Full Idea: Reason requires that we avoid multiplying hypotheses or principles, in somewhat the same way that the simplest system is always preferred in astronomy. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], 5) | |
| A reaction: He offers this principle without mentioning Ockham, as if it were self-evident. |
| 12711 | The immediate cause of movements is more real [than geometry] [Leibniz] |
| Full Idea: The force or proximate cause of these changes [of position] is something more real, and there is sufficient basis to attribute it to one body more than to another. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §18), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 3 | |
| A reaction: The force is said to be 'more real' than geometry. Leibniz seems to have embraced fairly physical powers in the period 1678-1698, and then seen them as more and more like spirits. |
| 19349 | The complete notion of a substance implies all of its predicates or attributes [Leibniz] |
| Full Idea: The nature of an individual substance or of a complete being is to have a notion so complete that it is sufficient to contain and to allow us to deduce from it all the predicates of the subject to which this notion is attributed. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §8) | |
| A reaction: This is the unusual Leibnizian view of such things, which he takes to extremes. I think it depends on whether you are talking of predicates, or of real intrinsic properties. I don't see how what happens to a substance can be contained in the subject. |
| 7558 | Substances mirror God or the universe, each from its own viewpoint [Leibniz] |
| Full Idea: Each substance is like a whole world, and like a mirror of God, or indeed of the whole universe, which each one expresses in its own fashion. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686]), quoted by Nicholas Jolley - Leibniz Intro | |
| A reaction: Leibniz isn't a pantheist, so he does not identify God with the universe, so it is a bit revealing that substance could reflect either one or the other, and he doesn't seem to care which. In the end, for all the sophistication, he just made it up. |
| 16761 | Forms are of no value in physics, but are indispensable in metaphysics [Leibniz] |
| Full Idea: The consideration of forms serves no purpose in the details of physics and must not be used to explain particular phenomena. …but their misuse must not lead us to reject something which is so useful to metaphysics. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], 10), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 24.5 | |
| A reaction: This is a key test for the question of whether metaphysics is separate from science (as Leibniz and Pasnau think), or whether there is a continuum. Is 'substantial form' an illuminating way to undestand modern physics? |
| 16065 | Constitution is identity (being in the same place), or it isn't (having different possibilities) [Wasserman] |
| Full Idea: Some insist that constitution is identity, on the grounds that distinct material objects cannot occupy the same place at the same time. Others argue that constitution is not identity, since the statue and its material differ in important respects. | |
| From: Ryan Wasserman (Material Constitution [2009], Intro) | |
| A reaction: The 'important respects' seem to concern possibilities rather than actualities, which is suspicious. It is misleading to think we are dealing with two things and their relation here. Objects must have constitutions; constitutions make objects. |
| 16067 | Constitution is not identity, because it is an asymmetric dependence relation [Wasserman] |
| Full Idea: For those for whom 'constitution is not identity' (the 'constitution view'), constitution is said to be an asymmetric relation, and also a dependence relation (unlike identity). | |
| From: Ryan Wasserman (Material Constitution [2009], 2) | |
| A reaction: It seems obvious that constitution is not identity, because there is more to a thing's identity than its mere constitution. But this idea makes it sound as if constitution has nothing to do with identity (chalk and cheese), and that can't be right. |
| 16069 | There are three main objections to seeing constitution as different from identity [Wasserman] |
| Full Idea: The three most common objections to the constitution view are the Impenetrability Objection (two things in one place?), the Extensionality Objection (mereology says wholes are just their parts), and the Grounding Objection (their ground is the same). | |
| From: Ryan Wasserman (Material Constitution [2009], 2) | |
| A reaction: [summary] He adds a fourth, that if two things can be in one place, why stop at two? [Among defenders of the Constitution View he lists Baker, Fine, Forbes, Koslicki, Kripke, Lowe, Oderberg, N.Salmon, Shoemaker, Simons and Yablo.] |
| 16068 | The weight of a wall is not the weight of its parts, since that would involve double-counting [Wasserman] |
| Full Idea: We do not calculate the weight of something by summing the weights of all its parts - weigh bricks and the molecules of a wall and you will get the wrong result, since you have weighed some parts more than once. | |
| From: Ryan Wasserman (Material Constitution [2009], 2) | |
| A reaction: In fact the complete inventory of the parts of a thing is irrelevant to almost anything we would like to know about the thing. The parts must be counted at some 'level' of division into parts. An element can belong to many different sets. |
| 13088 | Subjects include predicates, so full understanding of subjects reveals all the predicates [Leibniz] |
| Full Idea: The subject-term must always include the predicate-term, in such a way that the man who understood the notion of the subject perfectly would also judge that the predicate belongs to it. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §8) | |
| A reaction: Sounds as if every sentence is analytic, but he doesn't mean that. He does, oddly, mean that if we fully understand the name 'Alexander', we understand his complete history, which is a bit silly, I'm afraid. Even God doesn't learn things just from names. |
| 16074 | Relative identity may reject transitivity, but that suggests that it isn't about 'identity' [Wasserman] |
| Full Idea: If the relative identity theorist denies transitivity (to deal with the Ship of Theseus, for example), this would make us suspect that relativised identity relations are not identity relations, since transitivity seems central to identity. | |
| From: Ryan Wasserman (Material Constitution [2009], 6) | |
| A reaction: The problem here, I think, focuses on the meaning of the word 'same'. One change of plank leaves you with the same ship, but that is not transitive. If 'identical' is too pure to give the meaning of 'the same' it's not much use in discussing the world. |
| 13085 | Leibniz is some form of haecceitist [Leibniz, by Cover/O'Leary-Hawthorne] |
| Full Idea: Some form of haecceitism is central to the Leibnizian metaphysic. | |
| From: report of Gottfried Leibniz (Discourse on Metaphysics [1686], §8) by Cover,J/O'Leary-Hawthorne,J - Substance and Individuation in Leibniz 5.2.1 | |
| A reaction: That is, there is some inner hallmark that individuates each thing (though they don't mean the Duns Scotus idea of a haecceity which has no qualities apart from the capacity to individuate). Leibniz thinks essences individuate. |
| 5024 | Knowledge doesn't just come from the senses; we know the self, substance, identity, being etc. [Leibniz] |
| Full Idea: It is always false to say that all our notions come from the so-called external senses, for the notion I have of myself and of my thoughts, and consequently of being, substance, action, identity, and many others, come from an internal experience. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §27) | |
| A reaction: Of course, an empiricist like Hume would not deny this, as he bases his views on 'experience' (including anger, for example), not just 'sense experience'. But Hume, famously, said he has no experience of a Self, so can't get started on Leibniz's journey. |
| 4042 | Metaphysics requires the idea of people (speakers) located in space and time [Davidson] |
| Full Idea: An intelligible metaphysics will assign a central place to the idea of people (= speakers) with a location in public space and time. | |
| From: Donald Davidson (The Method of Truth in Metaphysics [1977], §III) | |
| A reaction: The 'location' is the interesting bit, requiring people to be bodies, not abstractions. A big, plausible claim, but hard to prove. |
| 5027 | If a person's memories became totally those of the King of China, he would be the King of China [Leibniz] |
| Full Idea: If someone were suddenly to become the King of China, forgetting what he has been, as if born anew, is this not as if he were annihilated, and a King of China created in his place at the same moment? | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §34) | |
| A reaction: Strikingly, this clearly endorse the view of the empiricist Locke. It is a view about the continuity of the self, not its essence, but Descartes must have turned in his grave when he read this. When this 'King of China' introspects his self, what is it? |
| 5023 | Future contingent events are certain, because God foresees them, but that doesn't make them necessary [Leibniz] |
| Full Idea: We must distinguish between what is certain and what is necessary; everyone agrees that future contingents are certain, since God foresees them, but it is not thereby admitted that they are necessary. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §13) | |
| A reaction: An interesting point, since there is presumably a difference between God foreseeing that future squares will have four corners, and His foreseeing the next war. It seems to me, though, that 'certainty' is bad enough news for free will, without necessity. |
| 2119 | People argue for God's free will, but it isn't needed if God acts in perfection following supreme reason [Leibniz] |
| Full Idea: People try to safeguard God's freedom, as though it were not freedom of the highest sort to act in perfection following sovereign reason. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §03) |
| 5025 | Mind and body can't influence one another, but God wouldn't intervene in the daily routine [Leibniz] |
| Full Idea: It is inconceivable that mind and body should have any influence on one another, and it is unreasonable simply to have recourse to the extraordinary operation of the universal cause in a matter which is ordinary and particular. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §33) | |
| A reaction: Leibniz was the ultimate intellectual contortionist! Here he is rejecting Cartesian interactionism, and also Malebranche's Occasionalism (God bridges the gap), in order to prepare for his own (daft) theory of what is now called Parallelism. |
| 4041 | Sentences held true determine the meanings of the words they contain [Davidson] |
| Full Idea: Sentences held true (the linguistic representatives of beliefs) determine the meanings of the words they contain. | |
| From: Donald Davidson (The Method of Truth in Metaphysics [1977], §II) | |
| A reaction: Maybe. Historically, truth and belief presumably precede words and sentences. But words separate off from beliefs very easily. I'm not convinced. Words initiate language, not beliefs? |
| 5026 | Animals lack morality because they lack self-reflection [Leibniz] |
| Full Idea: It is for lack of reflection on themselves that beasts have no moral qualities. | |
| From: Gottfried Leibniz (Discourse on Metaphysics [1686], §34) | |
| A reaction: Interesting, but I think this is false. I would say animals do have a sense of their self, because that is the most basic feature of any mind, but what they lack is second-order thought, that is, ability to reflect on and judge their own beliefs and acts. |