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All the ideas for 'Protagoras', 'The Logic of What Might Have Been' and 'Principles of Philosophy'

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63 ideas

1. Philosophy / D. Nature of Philosophy / 2. Invocation to Philosophy
The greatest good for a state is true philosophers [Descartes]
     Full Idea: The greatest good which can exist in a state is to have true philosophers.
     From: René Descartes (Principles of Philosophy [1646], Pref)
     A reaction: …because they understand true reality, especially the Good.
2. Reason / B. Laws of Thought / 4. Contraries
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.
4. Formal Logic / D. Modal Logic ML / 2. Tools of Modal Logic / b. Terminology of ML
A world is 'accessible' to another iff the first is possible according to the second [Salmon,N]
     Full Idea: A world w' is accessible to a consistent world w if and only if w' is possible in w. Being 'inaccessible to' or 'possible relative to' a consistent world is simply being possible according to that world, nothing more and nothing less.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
     A reaction: More illuminating than just saying that w can 'see' w'. Accessibility is internal to worIds. It gives some connection to why we spend time examining modal logic. There is no more important metaphysical notion than what is possible according to actuality.
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / d. System T
For metaphysics, T may be the only correct system of modal logic [Salmon,N]
     Full Idea: Insofar as modal logic is concerned exclusively with the logic of metaphysical modality, ..T may well be the one and only (strongest) correct system of (first-order) propositional logic.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], Intro)
     A reaction: This contrasts sharply with the orthodox view, that S5 (or at the very least S4) is the correct system for metaphysics.
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / f. System B
System B has not been justified as fallacy-free for reasoning on what might have been [Salmon,N]
     Full Idea: Even the conventionally accepted system B, which is weaker than S5 and independent of S4, has not been adequately justified as a fallacy-free system of reasoning about what might have been.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], Intro)
In B it seems logically possible to have both p true and p is necessarily possibly false [Salmon,N]
     Full Idea: The characteristic of B has the form φ⊃□◊φ. ...Even if these axioms are necessarily true, it seems logically possible for p to be true while the proposition that p is necessarily possible is at the same time false.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], Intro)
System B implies that possibly-being-realized is an essential property of the world [Salmon,N]
     Full Idea: Friends of B modal logic commit themselves to the loaded claim that it is logically true that the property of possibly being realized (or being a way things might have been) is an essential property of the world.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], V)
     A reaction: I think this 'loaded' formulation captures quite nicely the dispositional view I favour, that the possibilities of the actual world are built into the actual world, and define its nature just as much as the 'categorial' facts do.
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4
What is necessary is not always necessarily necessary, so S4 is fallacious [Salmon,N]
     Full Idea: We can say of a wooden table that it would have been possible for it to have originated from some different matter, even though it is not actually possible. So what is necessary fails to be necessarily necessary, and S4 modal logic is fallacious.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], I)
     A reaction: [compressed]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
S5 modal logic ignores accessibility altogether [Salmon,N]
     Full Idea: When we ignore accessibility altogether, we have finally zeroed in on S5 modal logic.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
S5 believers say that-things-might-have-been-that-way is essential to ways things might have been [Salmon,N]
     Full Idea: Believers in S5 as a correct system of propositional reasoning about what might have been must claim that it is an essential property of any way things might have been that things might have been that way.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], V)
     A reaction: Salmon is working in a view where you are probably safe to substitute 'necessary' for 'essential' without loss of meaning.
The unsatisfactory counterpart-theory allows the retention of S5 [Salmon,N]
     Full Idea: Counterpart-theoretic modal semantics allows for the retention of S5 modal propositional logic, at a considerable cost.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], V n18)
     A reaction: See the other ideas in this paper by Salmon for his general attack on S5 as the appropriate system for metaphysical necessity. He favours the very modest System T.
4. Formal Logic / D. Modal Logic ML / 4. Alethic Modal Logic
Metaphysical (alethic) modal logic concerns simple necessity and possibility (not physical, epistemic..) [Salmon,N]
     Full Idea: Metaphysical modal logic concerns metaphysical (or alethic) necessity and metaphysical (alethic) possibility, or necessity and possibility tout court - as opposed to such other types of modality as physical necessity, epistemic necessity etc.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], Intro n2)
8. Modes of Existence / C. Powers and Dispositions / 3. Powers as Derived
All powers can be explained by obvious features like size, shape and motion of matter [Descartes]
     Full Idea: There are no powers in stones and plants that are not so mysterious that they cannot be explained …from principles that are known to all and admitted by all, namely the shape, size, position, and motion of particles of matter.
     From: René Descartes (Principles of Philosophy [1646], IV.187), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 23.6
     A reaction: This is an invocation of 'categorical' properties, against dispositions. I take this to be quite wrong. The explanation goes the other way. What supports the structures; what drives the motion; what initiates anything?
8. Modes of Existence / D. Universals / 1. Universals
Five universals: genus, species, difference, property, accident [Descartes]
     Full Idea: The five commonly enumerated universals are: genus, species, difference, property and accident.
     From: René Descartes (Principles of Philosophy [1646], I.59)
     A reaction: Interestingly, this seems to be Descartes passing on his medieval Aristotelian inheritance, in which things are defined by placing them in a class, and then noting what distinguishes them within that class.
8. Modes of Existence / D. Universals / 6. Platonic Forms / c. Self-predication
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)
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
A universal is a single idea applied to individual things that are similar to one another [Descartes]
     Full Idea: Universals arise solely from the fact that we avail ourselves of one idea in order to think of all individual things that have a certain similitude. When we understand under the same name all the objects represented by this idea, that name is universal.
     From: René Descartes (Principles of Philosophy [1646], I.59)
     A reaction: Judging by the boldness of the pronouncement, it looks as if Descartes hasn't recognised the complexity of the problem. How do we spot a 'similarity', especially an abstraction like 'tool' or 'useful'? This sounds like Descartes trying to avoid Platonism.
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
If we perceive an attribute, we infer the existence of some substance [Descartes]
     Full Idea: Based on perceiving the presence of some attribute, we conclude there must also be present an existing thing or substance to which it can be attributed.
     From: René Descartes (Principles of Philosophy [1646], I.52), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 08.1
     A reaction: A rainbow might be a tricky case. This illustrates the persistent belief in substances, even among philosophers who embraced the new corpuscular and mechanistic view of matter.
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
A substance needs nothing else in order to exist [Descartes]
     Full Idea: By substance we can understand nothing else than a thing which so exists that it needs no other thing in order to exist.
     From: René Descartes (Principles of Philosophy [1646], I.51)
     A reaction: Properties, of course, are the things which have dependent existence. Can properties be reduced to substances (e.g. by adopting a materialist theory of mind)? Note that Descartes does not think that substances depend on God for existence.
9. Objects / D. Essence of Objects / 9. Essence and Properties
A substance has one principal property which is its nature and essence [Descartes]
     Full Idea: Each substance has one principal property that constitutes its nature and essence, to which all its other properties are referred. Extension in length, breadth, and depth constitutes the nature of corporeal substance; and thought of thinking substances.
     From: René Descartes (Principles of Philosophy [1646], I.53), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 08.3
     A reaction: Property is likely to be 'propria', which is a property distinctive of some thing, not just any old modern property. This is quite a strikingly original view of the nature of essence. Descartes despised 'substantial forms'.
9. Objects / D. Essence of Objects / 15. Against Essentialism
Any property is attached to anything in some possible world, so I am a radical anti-essentialist [Salmon,N]
     Full Idea: By admitting possible worlds of unlimited variation and recombination, I simply abandon true metaphysical essentialism. By my lights, any property is attached to anything in some possible world or other. I am a closet radical anti-essentialist.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], II)
     A reaction: Salmon includes impossible worlds within his scheme of understanding. It strikes me that this is metaphysical system which tells us nothing about how things are: it is sort of 'logical idealist'. Later he talks of 'we essentialists'.
10. Modality / A. Necessity / 3. Types of Necessity
Logical possibility contains metaphysical possibility, which contains nomological possibility [Salmon,N]
     Full Idea: Just as nomological possibility is a special kind of metaphysical possibility, so metaphysical possibility is a special kind of logical possibility.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], III)
     A reaction: This is the standard view of how the three types of necessity are nested. He gives a possible counterexample in footnote 7.
10. Modality / A. Necessity / 5. Metaphysical Necessity
In the S5 account, nested modalities may be unseen, but they are still there [Salmon,N]
     Full Idea: The S5 theorist's miscontrual of English (in the meaning of 'possibly possible') makes nested modality unseen, but it does not make nested modality vanish. Inaccessible worlds are still worlds.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
Metaphysical necessity is said to be unrestricted necessity, true in every world whatsoever [Salmon,N]
     Full Idea: It is held that it is the hallmark of metaphysical necessity is that it is completely unrestricted, the limiting case of restricted necessity, with no restrictions whatever. A proposition is necessary only if it is true in absolutely every world whatever.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], II)
     A reaction: This is the standard picture which leads to the claim that S5 modal logic is appropriate for metaphysical necessity, because there are no restrictions on accessibility. Salmon raises objections to this conventional view.
Bizarre identities are logically but not metaphysically possible, so metaphysical modality is restricted [Salmon,N]
     Full Idea: Though there is a way things logically could be according to which I am a credit card account, there is no way things metaphysically might be according to which I am a credit card account. This illustrates the restricted nature of metaphysical modality.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], III)
     A reaction: His drift is that metaphyical modality is restricted, but expressing it in S5 modal logic (where all worlds see one another) makes it unrestricted, so S5 logic is wrong for metaphysics. I'm impressed by his arguments.
Without impossible worlds, the unrestricted modality that is metaphysical has S5 logic [Salmon,N]
     Full Idea: If one confines one's sights to genuinely possible worlds, disavowing the impossible worlds, then metaphysical modality emerges as the limiting case - the 'unrestricted' modality that takes account of 'every' world - and S5 emerges as its proper logic.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
     A reaction: He observes that this makes metaphysical modality 'restricted' simply because you have restricted what 'all worlds' means. Could there be non-maximal worlds? Are logical and metaphysical modality coextensive? I think I like the S5 view.
Metaphysical necessity is NOT truth in all (unrestricted) worlds; necessity comes first, and is restricted [Salmon,N]
     Full Idea: A mythology gave us the idea that metaphysical necessity is truth in every world whatsoever, without restriction. But the notion of metaphysical modality comes first, and, like every notion of modality, it is restricted.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
10. Modality / A. Necessity / 6. Logical Necessity
Logical necessity is free of constraints, and may accommodate all of S5 logic [Salmon,N]
     Full Idea: With its freedom from the constraint of metaphysical possibility, logical necessity may be construed as accommodating all the axioms and rules of S5.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], III)
     A reaction: He goes on to raise problems for this simple thought. The big question: what are the limits of what is actually possible? Compare: what are the limits of what is imaginable? what are the limits of what is meaningfully sayable?
10. Modality / A. Necessity / 7. Natural Necessity
Nomological necessity is expressed with intransitive relations in modal semantics [Salmon,N]
     Full Idea: Intransitive relations are introduced into modal semantics for the purposes of interpreting various 'real' or restricted types of modalities, such as nomological necessity.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], II)
     A reaction: The point here is that the (so-called) 'laws of nature' are held to change from world to world, so necessity in one could peter out in some more remote world, rather than being carried over everywhere. A very Humean view of such things.
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Necessity and possibility are not just necessity and possibility according to the actual world [Salmon,N]
     Full Idea: The real meanings of the simple modal terms 'necessary' and 'possible' are not the same as the concepts of actual necessity and actual possibility, necessity and possibility according to the actual world.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
     A reaction: If you were an 'actualist' (who denies everything except the actual world) then you are unlikely to agree with this. In unrestricted possible worlds, being true in one world makes it possible in all worlds. So actual necessity is possible everywhere.
10. Modality / E. Possible worlds / 1. Possible Worlds / b. Impossible worlds
Impossible worlds are also ways for things to be [Salmon,N]
     Full Idea: Total ways things cannot be are also 'worlds', or maximal ways for things to be. They are impossible worlds.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], I)
     A reaction: This unorthodox view doesn't sound too plausible to me. To think of a circular square as a 'way things could be' sounds pretty empty, and mere playing with words. The number 7 could be the Emperor of China?
Denial of impossible worlds involves two different confusions [Salmon,N]
     Full Idea: Every argument I am aware of against impossible worlds confuses ways for things to be with ways things might have been, or worse, confuses ways things cannot be with ways for things to be that cannot exist - or worse yet, commits both errors.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], III)
     A reaction: He is claiming that 'ways for things to be' allows impossible worlds, whereas 'ways things might have been' appears not to. (I think! Read the paragraph yourself!)
Without impossible worlds, how things might have been is the only way for things to be [Salmon,N]
     Full Idea: If one ignores impossible worlds, then ways things might have been are the only ways for things to be that are left.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
     A reaction: Impossible worlds are included in 'ways for things to be', but excluded from 'ways things might have been'. I struggle with a circle being square as a 'way for circles to be'. I suppose being the greatest philosopher is a way for me to be.
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
Possible worlds rely on what might have been, so they can' be used to define or analyse modality [Salmon,N]
     Full Idea: On my conception, the notions of metaphysical necessity and possibility are not defined or analyzed in terms of the apparatus of possible worlds. The order of analysis is just the reverse: possible worlds rely on the notion of what might have been.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], IV)
     A reaction: This view seems to be becoming the new orthodoxy, and I certainly agree with it. I have no idea how you can begin to talk about possible worlds if you don't already have some idea of what 'possible' means.
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
Possible worlds are maximal abstract ways that things might have been [Salmon,N]
     Full Idea: I conceive of possible worlds as certain sorts of maximal abstract entities according to which certain things (facts, states of affairs) obtain and certain other things do not obtain. They are total ways things might have been.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], I)
Possible worlds just have to be 'maximal', but they don't have to be consistent [Salmon,N]
     Full Idea: As far as I can tell, worlds need not be logically consistent. The only restriction on worlds is that they must be (in some sense) 'maximal' ways for things to be.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], I)
     A reaction: The normal idea of a maximal model is that it must contain either p or ¬p, and not both, so I don't think I understand this thought, but I pass it on.
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / c. Worlds as propositions
You can't define worlds as sets of propositions, and then define propositions using worlds [Salmon,N]
     Full Idea: It is not a good idea to think of possible worlds as sets of propositions, and at the same time to think of propositions as sets of possible worlds.
     From: Nathan Salmon (The Logic of What Might Have Been [1989], I n3)
     A reaction: Salmon favours thinking of worlds as sets of propositions, and hence rejects the account of propositions as sets of worlds. He favours the 'Russellian' view of propositions, which seem to me to be the same as 'facts'.
11. Knowledge Aims / A. Knowledge / 3. Value of Knowledge
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.
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.
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
Total doubt can't include your existence while doubting [Descartes]
     Full Idea: He who decides to doubt everything cannot nevertheless doubt that he exists while he doubts.
     From: René Descartes (Principles of Philosophy [1646], Pref)
I think, therefore I am, because for a thinking thing to not exist is a contradiction [Descartes]
     Full Idea: There is a contradiction in conceiving that what thinks does not (at the same time as it thinks) exist. Hence this conclusion I think, therefore I am, is the first and most certain that occurs to one who philosophises in an orderly way.
     From: René Descartes (Principles of Philosophy [1646], I.07)
     A reaction: The classic statement of his argument. The significance here is that it seems to have the structure of an argument, as it involves 'philosophising', which leads to a 'contradiction', and hence to the famous conclusion. It is not just intuitive.
'Thought' is all our conscious awareness, including feeling as well as understanding [Descartes]
     Full Idea: By the word 'thought' I understand everything we are conscious of as operating in us. And that is why not only understanding, willing, imagining, but also feeling, are here the same thing as thinking.
     From: René Descartes (Principles of Philosophy [1646], I.09)
     A reaction: There is a bit of tension here between Descartes' correct need to include feeling in thought for his Cogito argument, and his tendency to dismiss animal consciousness, on the grounds that they only sense things, and don't make judgements.
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
'Nothing comes from nothing' is an eternal truth found within the mind [Descartes]
     Full Idea: The proposition 'nothing comes from nothing' is not to be considered as an existing thing, or the mode of a thing, but as a certain eternal truth which has its seat in our mind and is a common notion or axiom.
     From: René Descartes (Principles of Philosophy [1646], I.49)
     A reaction: There is a tension here, in his assertion that it is 'eternal', but 'not existing'. How does one distinguish an innate idea from an innate truth? 'Eternal' sounds like an external guarantee of truth, but being 'in our mind' sounds less reliable.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
We can know basic Principles without further knowledge, but not the other way round [Descartes]
     Full Idea: It is on the Principles, or first causes, that the knowledge of other things depends, so the Principles can be known without these last, but the other things cannot reciprocally be known without the Principles.
     From: René Descartes (Principles of Philosophy [1646], Pref)
     A reaction: A particularly strong assertion of foundationalism, as it says that not only must the foundations exist, but also we must actually know them. This sounds false, as elementary knowledge then seems to require far too much sophistication.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / b. Essence of consciousness
We can understand thinking occuring without imagination or sensation [Descartes]
     Full Idea: We can understand thinking without imagination or sensation, as is quite clear to anyone who attends to the matter.
     From: René Descartes (Principles of Philosophy [1646], I.53)
     A reaction: We may certainly take it that Descartes means if it is understandable then it is logically possible. To believe that thinking could occur without imagination strikes me as an astonishing error. I take imagination to be more central than understanding.
15. Nature of Minds / C. Capacities of Minds / 7. Seeing Resemblance
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)
16. Persons / D. Continuity of the Self / 7. Self and Thinking
In thinking we shut ourselves off from other substances, showing our identity and separateness [Descartes]
     Full Idea: Because each one of us understands what he thinks, and that in thinking he can shut himself off from every other substance, we may conclude that each of us is really distinct from every other thinking substance and from corporeal substance.
     From: René Descartes (Principles of Philosophy [1646], I.60)
     A reaction: This seems to be a novel argument which requires elucidation. I can 'shut myself off from every other substance'? If I shut myself off from thinking about food, does that mean hunger is not part of me? Or convince yourself that you don't have a brother?
16. Persons / F. Free Will / 1. Nature of Free Will
Our free will is so self-evident to us that it must be a basic innate idea [Descartes]
     Full Idea: It is so evident that we are possessed of a free will that can give or withhold its assent, that this may be counted as one of the first and most common notions found innately in us.
     From: René Descartes (Principles of Philosophy [1646], I.39)
     A reaction: It seems to me plausible to say that we have an innate conception of our own will (our ability to make decisions), though Hume says we only learn about the will from experience, but the idea that it is absolutely 'free' might never cross our minds.
17. Mind and Body / A. Mind-Body Dualism / 1. Dualism
There are two ultimate classes of existence: thinking substance and extended substance [Descartes]
     Full Idea: I observe two ultimate classes of things: intellectual or thinking things, pertaining to the mind or to thinking substance, and material things, pertaining to extended substance or to body.
     From: René Descartes (Principles of Philosophy [1646], I.48)
     A reaction: This is clear confirmation that Descartes believed the mind is a substance, rather than an insubstantial world of thinking. It leaves open the possibility of a different theory: that mind is not a substance, but is a Platonic adjunct to reality.
17. Mind and Body / D. Property Dualism / 5. Supervenience of mind
Even if tightly united, mind and body are different, as God could separate them [Descartes]
     Full Idea: Even if we suppose God had united a body and a soul so closely that they couldn't be closer, and made a single thing out of the two, they would still remain distinct, because God has the power of separating them, or conserving out without the other.
     From: René Descartes (Principles of Philosophy [1646], I.60)
     A reaction: If Descartes lost his belief in God (after discussing existence with Kant) would he cease to be a dualist? This quotation seems to be close to conceding a mind-body relationship more like supervenience than interaction.
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
Most errors of judgement result from an inaccurate perception of the facts [Descartes]
     Full Idea: What usually misleads us is that we very frequently form a judgement although we do not have an accurate perception of what we judge.
     From: René Descartes (Principles of Philosophy [1646], I.33)
     A reaction: This seems to me a generally accurate observation, particularly in the making of moral judgements (which was probably not what Descartes was considering). The implication is that judgements are to a large extent forced by our perceptions.
20. Action / C. Motives for Action / 3. Acting on Reason / b. Intellectualism
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)
20. Action / C. Motives for Action / 4. Responsibility for Actions
We do not praise the acts of an efficient automaton, as their acts are necessary [Descartes]
     Full Idea: We do not praise automata, although they respond exactly to the movements they were designed to produce, since their actions are performed necessarily
     From: René Descartes (Principles of Philosophy [1646], I.37)
     A reaction: I say we attribute responsibility when we perceive something like a 'person' as causing them. We don't blame small animals, because there is 'no one at home', but we blame children as they develop a full character and identity. We can ignore free will.
The greatest perfection of man is to act by free will, and thus merit praise or blame [Descartes]
     Full Idea: That the will should extend widely accords with its nature, and it is the greatest perfection in man to be able to act by its means, that is, freely, and by so doing we are in peculiar way masters of our actions, and thereby merit praise or blame.
     From: René Descartes (Principles of Philosophy [1646], I.37)
     A reaction: This seems to me to be a deep-rooted and false understanding which philosophy has inherited from theology. It doesn't strike me that there must an absolute 'buck-stop' to make us responsible. Why is it better for a decision to appear out of nowhere?
22. Metaethics / B. Value / 2. Values / j. Evil
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.
22. Metaethics / C. The Good / 1. Goodness / h. Good as benefit
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.
22. Metaethics / C. The Good / 3. Pleasure / c. Value of pleasure
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.
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.
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / d. Teaching virtue
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)
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)
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)
26. Natural Theory / A. Speculations on Nature / 1. Nature
Physics only needs geometry or abstract mathematics, which can explain and demonstrate everything [Descartes]
     Full Idea: I do not accept or desire any other principle in physics than in geometry or abstract mathematics, because all the phenomena of nature may be explained by their means, and sure demonstrations can be given of them.
     From: René Descartes (Principles of Philosophy [1646], 2.64), quoted by Peter Alexander - Ideas, Qualities and Corpuscles 7
     A reaction: This is his famous and rather extreme view, which might be described as hyper-pythagoreanism (by adding geometry to numbers). It seems to leave out matter, forces and activity.
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / c. Purpose denied
We will not try to understand natural or divine ends, or final causes [Descartes]
     Full Idea: We will not seek for the reason of natural things from the end which God or nature has set before him in their creation .
     From: René Descartes (Principles of Philosophy [1646], §28)
     A reaction: Teleology is more relevant to biology than to the other sciences, and it is hard to understand an eye without a notion of 'what it is for'. Planetary motion reveals nothing about purposes. If you demand a purpose, it becomes more baffling.
26. Natural Theory / A. Speculations on Nature / 7. Later Matter Theories / c. Matter as extension
Matter is not hard, heavy or coloured, but merely extended in space [Descartes]
     Full Idea: The nature of matter, or body viewed as a whole, consists not in its being something which is hard, heavy, or colored, or which in any other way affects the senses, but only in its being a thing extended in length, breadth and depth.
     From: René Descartes (Principles of Philosophy [1646], 2.4), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 04.5