82 ideas
17240 | Definitions are the first step in philosophy [Hobbes] |
Full Idea: In beginning philosophy, the first beginning is from definitions. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.15) | |
A reaction: Note that he doesn't say that definitions are the aim of philosophy, as some analysts might think. |
224 | When questions are doubtful we should concentrate not on objects but on ideas of the intellect [Plato] |
Full Idea: Doubtful questions should not be discussed in terms of visible objects or in relation to them, but only with reference to ideas conceived by the intellect. | |
From: Plato (Parmenides [c.364 BCE], 135e) |
6950 | You can be rational with undetected or minor inconsistencies [Harman] |
Full Idea: Rationality doesn't require consistency, because you can be rational despite undetected inconsistencies in beliefs, and it isn't always rational to respond to a discovery of inconsistency by dropping everything in favour of eliminating that inconsistency. | |
From: Gilbert Harman (Rationality [1995], 1.2) | |
A reaction: This strikes me as being correct, and is (I am beginning to realise) a vital contribution made to our understanding by pragmatism. European thinking has been too keen on logic as the model of good reasoning. |
6954 | A coherent conceptual scheme contains best explanations of most of your beliefs [Harman] |
Full Idea: A set of unrelated beliefs seems less coherent than a tightly organized conceptual scheme that contains explanatory principles that make sense of most of your beliefs; this is why inference to the best explanation is an attractive pattern of inference. | |
From: Gilbert Harman (Rationality [1995], 1.5.2) | |
A reaction: I find this a very appealing proposal. The central aim of rational thought seems to me to be best explanation, and I increasingly think that most of my beliefs rest on their apparent coherence, rather than their foundations. |
232 | Opposites are as unlike as possible [Plato] |
Full Idea: Opposites are as unlike as possible. | |
From: Plato (Parmenides [c.364 BCE], 159a) |
8937 | Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic [Hegel on Plato] |
Full Idea: Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic. | |
From: comment on Plato (Parmenides [c.364 BCE]) by Georg W.F.Hegel - Phenomenology of Spirit Pref 71 | |
A reaction: It is a long way from the analytic tradition of philosophy to be singling out a classic text for its 'artistic' achievement. Eventually we may even look back on, say, Kripke's 'Naming and Necessity' and see it in that light. |
17237 | Definitions of things that are caused must express their manner of generation [Hobbes] |
Full Idea: Definitions of things which may be understood to have some cause, must consist of such names as express the cause or manner of their generation, as when we define a circle to be a figure made by the circumduction of a straight line in a plane etc. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.13) | |
A reaction: His account of the circle is based on its mode of construction, which is the preferred account of Euclid, rather than a statement of its pure nature. |
17239 | Definition is resolution of names into successive genera, and finally the difference [Hobbes] |
Full Idea: The definition is nothing but a resolution of the name into its most universal parts; ...definitions of this kind always consist of genus and difference; the former names being all, till the last, general; and the last of all, difference. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.14) | |
A reaction: This is basically the scholastic Aristotelian view of definition. Note that Hobbes explicitly denies that the last step of the definition is general in character. |
17241 | A defined name should not appear in the definition [Hobbes] |
Full Idea: A defined name ought not to be repeated in the definition. ...No total can be part of itself. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.15) |
17242 | 'Petitio principii' is reusing the idea to be defined, in disguised words [Hobbes] |
Full Idea: 'Petitio principii' is when the conclusion to be proved is disguised in other words, and put for the definition or principle from whence it is to be demonstrated. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.18) |
17245 | A part of a part is a part of a whole [Hobbes] |
Full Idea: A part of a part is a part of a whole. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.07.09) |
13986 | Plato found antinomies in ideas, Kant in space and time, and Bradley in relations [Plato, by Ryle] |
Full Idea: Plato (in 'Parmenides') shows that the theory that 'Eide' are substances, and Kant that space and time are substances, and Bradley that relations are substances, all lead to aninomies. | |
From: report of Plato (Parmenides [c.364 BCE]) by Gilbert Ryle - Are there propositions? 'Objections' |
14150 | Plato's 'Parmenides' is perhaps the best collection of antinomies ever made [Russell on Plato] |
Full Idea: Plato's 'Parmenides' is perhaps the best collection of antinomies ever made. | |
From: comment on Plato (Parmenides [c.364 BCE]) by Bertrand Russell - The Principles of Mathematics §337 |
17258 | If we just say one, one, one, one, we don't know where we have got to [Hobbes] |
Full Idea: By saying one, one, one, one, and so forward, we know not what number we are at beyond two or three. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.12.05) | |
A reaction: This makes ordinals sound like meta-numbers. |
16150 | One is, so numbers exist, so endless numbers exist, and each one must partake of being [Plato] |
Full Idea: If one is, there must also necessarily be number - Necessarily - But if there is number, there would be many, and an unlimited multitude of beings. ..So if all partakes of being, each part of number would also partake of it. | |
From: Plato (Parmenides [c.364 BCE], 144a) | |
A reaction: This seems to commit to numbers having being, then to too many numbers, and hence to too much being - but without backing down and wondering whether numbers had being after all. Aristotle disagreed. |
229 | The one was and is and will be and was becoming and is becoming and will become [Plato] |
Full Idea: The one was and is and will be and was becoming and is becoming and will become. | |
From: Plato (Parmenides [c.364 BCE], 155d) |
21821 | Plato's Parmenides has a three-part theory, of Primal One, a One-Many, and a One-and-Many [Plato, by Plotinus] |
Full Idea: The Platonic Parmenides is more exact [than Parmenides himself]; the distinction is made between the Primal One, a strictly pure Unity, and a secondary One which is a One-Many, and a third which is a One-and-Many. | |
From: report of Plato (Parmenides [c.364 BCE]) by Plotinus - The Enneads 5.1.08 | |
A reaction: Plotinus approves of this three-part theory. Parmenides has the problem that the highest Being contains no movement. By placing the One outside Being you can give it powers which an existent thing cannot have. Cf the concept of God. |
17253 | Change is nothing but movement [Hobbes] |
Full Idea: All mutation consists in motion only | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.09.06) | |
A reaction: Another little gem of simplicity from Hobbes, and one with which I am inclined to agree. The value of a variable can 'change', but that may be metaphorical. |
221 | Absolute ideas, such as the Good and the Beautiful, cannot be known by us [Plato] |
Full Idea: The absolute good and the beautiful and all which we conceive to be absolute ideas are unknown to us. | |
From: Plato (Parmenides [c.364 BCE], 134c) |
16670 | Accidents are just modes of thinking about bodies [Hobbes] |
Full Idea: An accident is a mode of conceiving a body. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.02) | |
A reaction: In contrast to the other thinkers who followed Suárez on modes in the early 17th century, Hobbes thinks they are just ways of 'conceiving' bodies, rather than actual features of them. |
16621 | Accidents are not parts of bodies (like blood in a cloth); they have accidents as things have a size [Hobbes] |
Full Idea: An accident's being in a body is not to be taken as something contained in that body - as if redness were in blood like blood in a bloody cloth, as part of the whole, for then accident would be a body. It is like body having size or rest or movement. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.03) | |
A reaction: [compressed] Hobbes is fishing for something like the Quinean view of properties, but no one seems to be able to articulate this sceptical view very well. Pasnau says he means to talk of 'the mode of conceiving a body' (De C 8.2). |
16734 | The complete power of an event is just the aggregate of the qualities that produced it [Hobbes] |
Full Idea: The power of agent and patient taken together, which may be called the complete power, is the same as the complete cause, for each consists in the aggregation together of all the accidents that are required to produce an effect in both agent and patient. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.10.01) | |
A reaction: They treat powers as macro phenomena, and don't seem to have a sense of the basic powers that build up the big picture. |
227 | You must always mean the same thing when you utter the same name [Plato] |
Full Idea: You must always mean the same thing when you utter the same name. | |
From: Plato (Parmenides [c.364 BCE], 147d) |
223 | If you deny that each thing always stays the same, you destroy the possibility of discussion [Plato] |
Full Idea: If a person denies that the idea of each thing is always the same, he will utterly destroy the power of carrying on discussion. | |
From: Plato (Parmenides [c.364 BCE], 135c) |
210 | It would be absurd to think there were abstract Forms for vile things like hair, mud and dirt [Plato] |
Full Idea: Are there abstract ideas for such things as hair, mud and dirt, which are particularly vile and worthless? That would be quite absurd. | |
From: Plato (Parmenides [c.364 BCE], 130d) |
220 | The concept of a master includes the concept of a slave [Plato] |
Full Idea: Mastership in the abstract is mastership of slavery in the abstract. | |
From: Plato (Parmenides [c.364 BCE], 133e) |
211 | If admirable things have Forms, maybe everything else does as well [Plato] |
Full Idea: It is troubling that if admirable things have abstract ideas, then perhaps everything else must have ideas as well. | |
From: Plato (Parmenides [c.364 BCE], 130d) |
219 | If absolute ideas existed in us, they would cease to be absolute [Plato] |
Full Idea: None of the absolute ideas exists in us, because then it would no longer be absolute. | |
From: Plato (Parmenides [c.364 BCE], 133c) |
228 | Greatness and smallness must exist, to be opposed to one another, and come into being in things [Plato] |
Full Idea: These two ideas, greatness and smallness, exist, do they not? For if they did not exist, they could not be opposites of one another, and could not come into being in things. | |
From: Plato (Parmenides [c.364 BCE], 149e) |
16151 | Plato moves from Forms to a theory of genera and principles in his later work [Plato, by Frede,M] |
Full Idea: It seems to me that Plato in the later dialogues, beginning with the second half of 'Parmenides', wants to substitute a theory of genera and theory of principles that constitute these genera for the earlier theory of forms. | |
From: report of Plato (Parmenides [c.364 BCE]) by Michael Frede - Title, Unity, Authenticity of the 'Categories' V | |
A reaction: My theory is that the later Plato came under the influence of the brilliant young Aristotle, and this idea is a symptom of it. The theory of 'principles' sounds like hylomorphism to me. |
212 | The whole idea of each Form must be found in each thing which participates in it [Plato] |
Full Idea: The whole idea of each form (of beauty, justice etc) must be found in each thing which participates in it. | |
From: Plato (Parmenides [c.364 BCE], 131a) |
218 | Participation is not by means of similarity, so we are looking for some other method of participation [Plato] |
Full Idea: Participation is not by means of likeness, so we must seek some other method of participation. | |
From: Plato (Parmenides [c.364 BCE], 133a) |
213 | Each idea is in all its participants at once, just as daytime is a unity but in many separate places at once [Plato] |
Full Idea: Just as day is in many places at once, but not separated from itself, so each idea might be in all its participants at once. | |
From: Plato (Parmenides [c.364 BCE], 131b) |
216 | If things are made alike by participating in something, that thing will be the absolute idea [Plato] |
Full Idea: That by participation in which like things are made like, will be the absolute idea, will it not? | |
From: Plato (Parmenides [c.364 BCE], 132e) |
215 | If things partake of ideas, this implies either that everything thinks, or that everything actually is thought [Plato] |
Full Idea: If all things partake of ideas, must either everything be made of thoughts and everything thinks, or everything is thought, and so can't think? | |
From: Plato (Parmenides [c.364 BCE], 132c) |
217 | Nothing can be like an absolute idea, because a third idea intervenes to make them alike (leading to a regress) [Plato] |
Full Idea: It is impossible for anything to be like an absolute idea, because a third idea will appear to make them alike, and if that is like anything, it will lead to another idea, and so on. | |
From: Plato (Parmenides [c.364 BCE], 133a) |
214 | If absolute greatness and great things are seen as the same, another thing appears which makes them seem great [Plato] |
Full Idea: If you regard the absolute great and the many great things in the same way, will not another appear beyond, by which all these must appear to be great? | |
From: Plato (Parmenides [c.364 BCE], 132a) |
17247 | The only generalities or universals are names or signs [Hobbes] |
Full Idea: Nothing is general or universal besides names or signs. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.05) | |
A reaction: This is the perfect motto for nominalists, among which I am inclined to include myself. Hobbes had a fabulous gift for economy of phrasing. This website is dedicated to that ideal. Reality does not contain generalities (obviously!!). |
14960 | Bodies are independent of thought, and coincide with part of space [Hobbes] |
Full Idea: A body is that, which having no dependence on our thought, is coincident or coextended with some part of space. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.01) | |
A reaction: This rather Cartesian view doesn't seem to offer any distinction between empty space and space containing an 'object'. Presumably it is the ancestor of the Quinean account just in terms of space-time points. Don't like it. |
17250 | If you separate the two places of one thing, you will also separate the thing [Hobbes] |
Full Idea: One body cannot be in two places at the same time, ...for the place that a body fills being divided into two, the placed body will also be divided into two; the place and the body that fills that place are divided both together. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.08) | |
A reaction: If every time you manipulated one body it affected both of them, you might say that one body was in two places, rather like a mirror image. |
17249 | If you separated two things in the same place, you would also separate the places [Hobbes] |
Full Idea: Two bodies cannot be together in the same place, ..because when a body that fills its whole place is divided into two, the place itself is divided into two also, so that there will be two places. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.08) | |
A reaction: The wonderful things about philosophy is that you are faced with obvious truths of the world, and cannot begin to think why they are true - and then up steps a philosopher and offers you a reason. |
15851 | Parts must belong to a created thing with a distinct form [Plato] |
Full Idea: The part would not be the part of many things or all, but of some one character ['ideas'] and of some one thing, which we call a 'whole', since it has come to be one complete [perfected] thing composed [created] of all. | |
From: Plato (Parmenides [c.364 BCE], 157d) | |
A reaction: A serious shot by Plato at what identity is. Harte quotes it (125) and shows that 'character' is Gk 'idea', and 'composed' will translate as 'created'. 'Form' links this Platonic passage to Aristotle's hylomorphism. |
17248 | If a whole body is moved, its parts must move with it [Hobbes] |
Full Idea: How can any whole body be moved, unless all its parts be moved together with it? | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.05) | |
A reaction: This might be a distinguishing mark for a whole physical body. I think it is probably the main mark for ordinary folk. I've never found this idea in Aristotle. |
15846 | In Parmenides, if composition is identity, a whole is nothing more than its parts [Plato, by Harte,V] |
Full Idea: At the heart of the 'Parmenides' puzzles about composition is the thesis that composition is identity. Considered thus, a whole adds nothing to an ontology that already includes its parts | |
From: report of Plato (Parmenides [c.364 BCE]) by Verity Harte - Plato on Parts and Wholes 2.5 | |
A reaction: There has to be more to a unified identity that mere proximity of the parts. When do parts come together, and when do they actually 'compose' something? |
15849 | Plato says only a one has parts, and a many does not [Plato, by Harte,V] |
Full Idea: In 'Parmenides' it is argued that a part cannot be part of a many, but must be part of something one. | |
From: report of Plato (Parmenides [c.364 BCE], 157c) by Verity Harte - Plato on Parts and Wholes 3.2 | |
A reaction: This looks like the right way to go with the term 'part'. We presuppose a unity before we even talk of its parts, so we can't get into contradictions and paradoxes about their relationships. |
15850 | Anything which has parts must be one thing, and parts are of a one, not of a many [Plato] |
Full Idea: The whole of which the parts are parts must be one thing composed of many; for each of the parts must be part, not of a many, but of a whole. | |
From: Plato (Parmenides [c.364 BCE], 157c) | |
A reaction: This is a key move of metaphysics, and we should hang on to it. The other way madness lies. |
16790 | A body is always the same, whether the parts are together or dispersed [Hobbes] |
Full Idea: A body is always the same, whether the parts of it be put together or dispersed; or whether it be congealed or dissolved. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.07) | |
A reaction: This appears to be a commitment by Hobbes to what we now call 'classical' mereology - that any bunch of things can count as a whole, whether they are together or dispersed. He seems to mean more than a watch surviving dismantling. |
13259 | It seems that the One must be composed of parts, which contradicts its being one [Plato] |
Full Idea: The One must be composed of parts, both being a whole and having parts. So on both grounds the One would thus be many and not one. But it must be not many, but one. So if the One will be one, it will neither be a whole, nor have parts. | |
From: Plato (Parmenides [c.364 BCE], 137c09), quoted by Kathrin Koslicki - The Structure of Objects 5.2 | |
A reaction: This is the starting point for Plato's metaphysical discussion of objects. It seems to begin a line of thought which is completed by Aristotle, surmising that only an essential structure can bestow identity on a bunch of parts. |
17244 | To make a whole, parts needn't be put together, but can be united in the mind [Hobbes] |
Full Idea: In composition, it is to be understood that for the making up of a whole there is no need of putting the parts together, so as to make them touch one another, but only of collecting them into one sum in the mind. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.07.08) | |
A reaction: This seems to the 'unrestricted composition' of classical mereology, since it appears that Hobbes offers no restriction on which parts can be united by a mind, no matter how bizarre. |
17233 | Particulars contain universal things [Hobbes] |
Full Idea: Universal things are contained in the nature of singular things. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.04) | |
A reaction: That is the neatest and most accurate summary of the situation I have ever read. Particulars come first, but they are all riddled with generalities (but that is not as well said as Hobbes's remark). |
17246 | Some accidental features are permanent, unless the object perishes [Hobbes] |
Full Idea: There are certain accidents which can never perish except the body perish also. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.03) | |
A reaction: He is just making an observation, and not proposing a theory about essence. |
17251 | The feature which picks out or names a thing is usually called its 'essence' [Hobbes] |
Full Idea: That accident for which we give a certain name to any body, or the accident which denominates its subject, is commonly called the essence thereof. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.23) | |
A reaction: This is clearly a prelude to Locke's more carefully formulated 'nominal essence'. Fairly obvious, for nominalist empiricists. A bit surprising to say this was 'common'. |
17257 | It is the same river if it has the same source, no matter what flows in it [Hobbes] |
Full Idea: That will be the same river which flows from one and the same fountain, whether the same water, or other water, or something other than water, flow thence. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.07) | |
A reaction: This makes the source the one necessity for a river. I think the end matters too. If the Thames reversed direction, and flowed into Wales, it would not be the Thames any more. |
12853 | Some individuate the ship by unity of matter, and others by unity of form [Hobbes] |
Full Idea: In the Ship of Theseus, some place individuity in the unity of matter; others, in the unity of form. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.07) | |
A reaction: Simons raises this comment into a dogma, that there are at least two objects present in the ship. If I offered you a sum for the contents of your house, they would have a unity of monetary value. |
17256 | If a new ship were made of the discarded planks, would two ships be numerically the same? [Hobbes] |
Full Idea: If some man kept the old planks as they were taken out, and by putting them afterwards together again in the same order, had again made a ship of them, ...there would have been two ships numerically the same, which is absurd. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.07) | |
A reaction: This is the origin of the famous modern problematical example of the Ship of Theseus. The ancient example is just the case of whether you step into the same river, but using an artefact with parts, to make it clearer. |
16794 | As an infant, Socrates was not the same body, but he was the same human being [Hobbes] |
Full Idea: It makes a great difference to ask concerning Socrates whether he is the same human being or whether he is the same body. For his body, when he is old, cannot be the same it was when he was an infant. …He can, however, be the same human being. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.07) | |
A reaction: This is not commitment to full (Geachian) relative identity, but it notes the problem. |
15847 | Two things relate either as same or different, or part of a whole, or the whole of the part [Plato] |
Full Idea: Everything is surely related to everything as follows: either it is the same or different; or, if it is not the same or different, it would be related as part to whole or as whole to part. | |
From: Plato (Parmenides [c.364 BCE], 146b) | |
A reaction: This strikes me as a really helpful first step in trying to analyse the nature of identity. Two things are either two or (actually) one, or related mereologically. |
17255 | Two bodies differ when (at some time) you can say something of one you can't say of the other [Hobbes] |
Full Idea: Two bodies are said to differ from one another, when something may be said of one of them, which cannot be said of the other at the same time. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.02) | |
A reaction: Note the astute addition of 'at the same time'. Note also that it is couched in terms of what is true, rather than in terms of 'properties' or 'accidents'. |
16582 | We can imagine a point swelling and contracting - but not how this could be done [Hobbes] |
Full Idea: Even if we can feign in our mind that a point swells to a huge bulk and then contracts to a point - imagining something's made from nothing (ex nihilo), and nothing's made from something - still we cannot comprehend how this could be done in nature. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.20) | |
A reaction: [compressed] Pasnau notes that this offers two sorts of conceivability, of something happening, and of a reason for it happening. A really nice idea, significant (I think) for scientific essentialists, who say possibilities are fewer than you think. |
6955 | Enumerative induction is inference to the best explanation [Harman] |
Full Idea: We might think of enumerative induction as inference to the best explanation, taking the generalization to explain its instances. | |
From: Gilbert Harman (Rationality [1995], 1.5.2) | |
A reaction: This is a helpful connection. The best explanation of these swans being white is that all swans are white; it ceased to be the best explanation when black swans turned up. In the ultimate case, a law of nature is the explanation. |
6952 | Induction is 'defeasible', since additional information can invalidate it [Harman] |
Full Idea: It is sometimes said that inductive reasoning is 'defeasible', meaning that considerations that support a given conclusion can be defeated by additional information. | |
From: Gilbert Harman (Rationality [1995], 1.4.5) | |
A reaction: True. The point is that being defeasible does not prevent such thinking from being rational. The rational part of it is to acknowledge that your conclusion is defeasible. |
6953 | All reasoning is inductive, and deduction only concerns implication [Harman] |
Full Idea: Deductive logic is concerned with deductive implication, not deductive reasoning; all reasoning is inductive | |
From: Gilbert Harman (Rationality [1995], 1.4.5) | |
A reaction: This may be an attempt to stipulate how the word 'reasoning' should be used in future. It is, though, a bold and interesting claim, given the reputation of induction (since Hume) of being a totally irrational process. |
17238 | Science aims to show causes and generation of things [Hobbes] |
Full Idea: The end of science is the demonstration of the causes and generation of things. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.13) |
17260 | Imagination is just weakened sensation [Hobbes] |
Full Idea: Imagination is nothing else but sense decaying or weakened by the absence of the object. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 4.25.07) | |
A reaction: This sounds more like memory than imagination. He needs to say something about unusual combinations of memories, I would have thought. |
19373 | A 'conatus' is an initial motion, experienced by us as desire or aversion [Hobbes, by Arthur,R] |
Full Idea: Hobbes' notion of 'conatus' is a 'beginning of motion' - a motion through a point of space in an instant of time. In a human subject this is experience as desire or aversion. It thus forms a bridge between physics and psychology. | |
From: report of Thomas Hobbes (De Corpore (Elements, First Section) [1655], p.178) by Richard T.W. Arthur - Leibniz 3 'Worlds' | |
A reaction: This sounds rather like the primitive concept of a power which I like, but the term seems to be used very vaguely, and never discussed carefully. The idea provoked Leibniz to connect physical force with mental life. |
2948 | Sensation is merely internal motion of the sentient being [Hobbes] |
Full Idea: Sense in the sentient, can be nothing else but motion in some of the internal parts of the sentient; and the parts so moved are parts of the organs of sense. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 3.15.02) | |
A reaction: Amazingly bold for the time, and presumably influenced by Lucretius. I am sympathetic, but to suggest that sensation is nothing more sounds a bit like a category mistake. Has he grasped that the brain is involved? |
17261 | Apart from pleasure and pain, the only emotions are appetite and aversion [Hobbes] |
Full Idea: All the passions, called passions of the mind, consist of appetite and aversion, except pure pleasure and pain. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 4.25.13) | |
A reaction: He now faces the challenge of explaining all the many other emotions in terms of these two. Good luck with that, Thomas. |
6951 | Ordinary rationality is conservative, starting from where your beliefs currently are [Harman] |
Full Idea: Ordinary rationality is generally conservative, in the sense that you start from where you are, with your present beliefs and intentions. | |
From: Gilbert Harman (Rationality [1995], 1.3) | |
A reaction: This stands opposed to the Cartesian or philosophers' rationality, which requires that (where possible) everything be proved from scratch. Harman seems right, that the normal onus of proof is on changing beliefs, rather proving you should retain them. |
17236 | Words are not for communication, but as marks for remembering what we have learned [Hobbes] |
Full Idea: The use of words consists in this, that they may serve for marks by which whatsoever we have found out may be recalled to memory ...but not as signs by which we declare the same to others. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.11) | |
A reaction: This exactly fits the idea of mental files, of which I am a fan. That this is the actual purpose of language is an unusual but interesting view. |
222 | Only a great person can understand the essence of things, and an even greater person can teach it [Plato] |
Full Idea: Only a man of very great natural gifts will be able to understand that everything has a class and absolute essence, and an even more wonderful man can teach this. | |
From: Plato (Parmenides [c.364 BCE], 135a) |
16600 | Prime matter is body considered with mere size and extension, and potential [Hobbes] |
Full Idea: Prime matter signifies body considered without the consideration of any form or accident except only magnitude or extension, and aptness to receive form and accidents. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.08.24) | |
A reaction: I take 'considered without' to indicate that he thinks of it as a psychological abstraction, rather than some actual existing thing. |
225 | The unlimited has no shape and is endless [Plato] |
Full Idea: The unlimited partakes neither of the round nor of the straight, because it has no ends nor edges. | |
From: Plato (Parmenides [c.364 BCE], 137e) |
2062 | The only movement possible for the One is in space or in alteration [Plato] |
Full Idea: If the One moves it either moves spatially or it is altered, since these are the only motions. | |
From: Plato (Parmenides [c.364 BCE], 138b) |
231 | Everything partakes of the One in some way [Plato] |
Full Idea: The others are not altogether deprived of the one, for they partake of it in some way. | |
From: Plato (Parmenides [c.364 BCE], 157c) | |
A reaction: Compare Idea 233. |
233 | Some things do not partake of the One [Plato] |
Full Idea: The others cannot partake of the one in any way; they can neither partake of it nor of the whole. | |
From: Plato (Parmenides [c.364 BCE], 159d) | |
A reaction: Compare Idea 231 |
17252 | Acting on a body is either creating or destroying a property in it [Hobbes] |
Full Idea: A body is said to work upon or act, that is to say, do something to another body, when it either generates or destroys some accident in it. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.09.01) |
17254 | An effect needs a sufficient and necessary cause [Hobbes] |
Full Idea: There can be no effect but from a sufficient and necessary cause. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.10.02) | |
A reaction: To be compared with Mackie's subtler modern account of this matter. If two different separate causes could lead to the same result, it is hard to see how the cause must be 'necessary' (unless you say they lead to different effects). |
17235 | A cause is the complete sum of the features which necessitate the effect [Hobbes] |
Full Idea: A cause it the sum or aggregate of all such accidents, both in the agents and in the patient, as concur to the producing of the effect propounded; all of which existing together, ti cannot be understood but that the effect existenth without them. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.10) | |
A reaction: For most causes we meet, this definition will include gravity and electro-magnetism, so it doesn't help in narrowing things down. Notice that he accepts the necessity, despite his committed empiricism. |
17234 | Motion is losing one place and acquiring another [Hobbes] |
Full Idea: Motion is privation of one place, and the acquisition of another. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 1.6.06) | |
A reaction: This is basically the 'at-at' theory of motion which empiricists like, because it breaks motion down into atoms of experience. Hobbes needs an ontology which includes 'places'. |
17259 | 'Force' is the quantity of movement imposed on something [Hobbes] |
Full Idea: I define 'force' to be the impetus or quickness of motion multiplied either into itself, or into the magnitude of the movent, by means of which whereof the said movent works more or less upon the body that resists it. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 3.15.02) | |
A reaction: Not very helpful, perhaps, but it shows a view of force at quite an early date, well before Newton. |
17243 | Past times can't exist anywhere, apart from in our memories [Hobbes] |
Full Idea: When people speak of the times of their predecessors, they do not think after their predecessors are gone that their times can be any where else than in the memory of those that remember. | |
From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.07.03) |
234 | We couldn't discuss the non-existence of the One without knowledge of it [Plato] |
Full Idea: There must be knowledge of the one, or else not even the meaning of the words 'if the one does not exist' would be known. | |
From: Plato (Parmenides [c.364 BCE], 160d) |