20 ideas
23367 | Even pointing a finger should only be done for a reason [Epictetus] |
Full Idea: Philosophy says it is not right even to stretch out a finger without some reason. | |
From: Epictetus (fragments/reports [c.57], 15) | |
A reaction: The key point here is that philosophy concerns action, an idea on which Epictetus is very keen. He rather despise theory. This idea perfectly sums up the concept of the wholly rational life (which no rational person would actually want to live!). |
18274 | Analysis complicates a statement, but only as far as the complexity of its meaning [Wittgenstein] |
Full Idea: Analysis makes the statement more complicated than it was; but it cannot and ought not to make it more complicated than its meaning (Bedeutung) was to begin with. When the statement is as complex as its meaning, then it is completely analysed. | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], 46e) | |
A reaction: But how do you assess how complex the 'Bedeutung' was before you started? |
16908 | We can dispense with self-evidence, if language itself prevents logical mistakes [Jeshion on Wittgenstein] |
Full Idea: The 'self-evidence' of which Russell talks so much can only be dispensed with in logic if language itself prevents any logical mistake. | |
From: comment on Ludwig Wittgenstein (Notebooks 1914-1916 [1915], 4) by Robin Jeshion - Frege's Notion of Self-Evidence 4 | |
A reaction: Jeshion presents this as a key idea, turning against Frege, and is the real source of the 'linguistic turn' in philosophy. If self-evidence is abandoned, then language itself is the guide to truth, so study language. I think I prefer Frege. See Quine? |
18276 | A statement's logical form derives entirely from its constituents [Wittgenstein] |
Full Idea: The logical form of the statement must already be given in the forms of its constituents. | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], 23e) | |
A reaction: This would evidently require each constituent to have a 'logical form'. It is hard to see what that could beyond its part of speech. Do two common nouns have the same logical form? |
6563 | 'And' and 'not' are non-referring terms, which do not represent anything [Wittgenstein, by Fogelin] |
Full Idea: Wittgenstein's 'fundamental idea' is that the 'and' and 'not' which guarantee the truth of "not p and not-p" are meaningful, but do not get their meaning by representing or standing for or referring to some kind of entity; they are non-referring terms. | |
From: report of Ludwig Wittgenstein (Notebooks 1914-1916 [1915], §37) by Robert Fogelin - Walking the Tightrope of Reason Ch.1 | |
A reaction: Wittgenstein then defines the terms using truth tables, to show what they do, rather than what they stand for. This seems to me to be a candidate for the single most important idea in the history of the philosophy of logic. |
15091 | Restrict 'logical truth' to formal logic, rather than including analytic and metaphysical truths [Shoemaker] |
Full Idea: I favour restricting the term 'logical truth' to what logicians would count as such, excluding both analytic truths like 'Bachelors are unmarried' and Kripkean necessities like 'Gold is an element'. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], I) | |
A reaction: I agree. There is a tendency to splash the phrases 'logical truth' and 'logical necessity around in vague ways. I take them to strictly arise out of the requirements of formal systems of logic. |
23472 | The sense of propositions relies on the world's basic logical structure [Wittgenstein] |
Full Idea: In order for a proposition to be CAPABLE of making sense, the world must already have the logical structure it has. The logic of the world is prior to all truth and falsehood. | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], p.14c) | |
A reaction: It seems that in Tractatus it is propositions about facts which are true or false, but prior to the facts are substance and the objects, and it is there that we find the logical structure of the world. I see this view as modern stoicism. |
15095 | A property's causal features are essential, and only they fix its identity [Shoemaker] |
Full Idea: The view I now favour says that the causal features of a property, both forward-looking and backward-looking, are essential to it. And it says that properties having the same causal features are identical. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], III) | |
A reaction: In this formulation we have essentialism about properties, as well as essentialism about the things which have the properties. |
15097 | I claim that a property has its causal features in all possible worlds [Shoemaker] |
Full Idea: The controversial claim of my theory is that the causal features of properties are essential to them - are features that they have in all possible worlds. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], III) | |
A reaction: One problem is that a property can come in degrees, so what degree of the property is necessary to it? It is better to assign this claim to the fundamental properties (which are best called 'powers'). |
15094 | I now deny that properties are cluster of powers, and take causal properties as basic [Shoemaker] |
Full Idea: I now reject the formulation of the causal theory which says that a property is a cluster of conditional powers. That has a reductionist flavour, which is a cheat. We need properties to explain conditional powers, so properties won't reduce. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], III) | |
A reaction: [compressed wording] I agree with Mumford and Anjum in preferring his earlier formulation. I think properties are broad messy things, whereas powers can be defined more precisely, and seem to have more stability in nature. |
15099 | If something is possible, but not nomologically possible, we need metaphysical possibility [Shoemaker] |
Full Idea: If it is possible that there could be possible states of affairs that are not nomologically possible, don't we therefore need a notion of metaphysical possibility that outruns nomological possibility? | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], VI) | |
A reaction: Shoemaker rejects this possibility (p.425). I sympathise. So there is 'natural' possibility (my preferred term), which is anything which stuff, if it exists, could do, and 'logical' possibility, which is anything that doesn't lead to contradiction. |
15101 | Once you give up necessity as a priori, causal necessity becomes the main type of necessity [Shoemaker] |
Full Idea: Once the obstacle of the deeply rooted conviction that necessary truths should be knowable a priori is removed, ...causal necessity is (pretheoretically) the very paradigm of necessity, in ordinary usage and in dictionaries. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], VII) | |
A reaction: The a priori route seems to lead to logical necessity, just by doing a priori logic, and also to metaphysical necessity, by some sort of intuitive vision. This is a powerful idea of Shoemaker's (implied, of course, in Kripke). |
15098 | Empirical evidence shows that imagining a phenomenon can show it is possible [Shoemaker] |
Full Idea: We have abundant empirical evidence that when we can imagine some phenomenal situation, e.g., imagine things appearing certain ways, such a situation could actually exist. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], VI) | |
A reaction: There seem to be good reasons for holding the opposite view too. We can imagine gold appearing to be all sorts of colours, but that doesn't make it possible. What does empirical evidence really tell us here? |
15100 | Imagination reveals conceptual possibility, where descriptions avoid contradiction or incoherence [Shoemaker] |
Full Idea: Imaginability can give us access to conceptual possibility, when we come to believe situations to be conceptually possible by reflecting on their descriptions and seeing no contradiction or incoherence. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], VI) | |
A reaction: If take the absence of contradiction to indicate 'logical' possibility, but the absence of incoherence is more interesting, even if it is a bit vague. He is talking of 'situations', which I take to be features of reality. A priori synthetic? |
23500 | My main problem is the order of the world, and whether it is knowable a priori [Wittgenstein] |
Full Idea: The great problem around which everything turns that I write is: is there an order in the world a priori, and if so what does it consist in? | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], 15.06.01) | |
A reaction: Morris identifies this as a 'Kantian question'. I trace it back to stoicism. This question has never bothered me. It just seems weird to think that you can infer reality from the examination of your own thinking. Perhaps I should take it more seriously? |
15096 | 'Grue' only has causal features because of its relation to green [Shoemaker] |
Full Idea: Perhaps 'grue' has causal features, but only derivatively, in virtue of its relation to green. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], III) | |
A reaction: I take grue to be a behaviour, and not a property at all. The problem only arises because the notion of a 'property' became too lax. Presumably Shoemaker should also mention blue in his account. |
22323 | The philosophical I is the metaphysical subject, the limit - not a part of the world [Wittgenstein] |
Full Idea: The philosophical I is not the man, not the human body, or the human soul of wh9ch psychology treats, but the metaphysical subject, the limit - not a part of the world. | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], 1916. 2 Sep), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 58 Intro | |
A reaction: This is to treat the self as a phenomenon of thought, rather than of a human being. So if a machine could think, would it hence necessarily have a metaphysical self? |
23481 | Propositions assemble a world experimentally, like the model of a road accident [Wittgenstein] |
Full Idea: In the proposition a world is as it were put together experimentally. (As when in the law court in Paris a motor-car accident is represented by means of dolls, etc). | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], 14.09.29) | |
A reaction: [see Tractatus 4.031] This is the first appearance of LW's picture (or model) theory of meaning. It may well be the best theory of meaning anyone has come up with, since meaning being out in the world strikes me as absurd. |
4678 | Absolute prohibitions are the essence of ethics, and suicide is the most obvious example [Wittgenstein] |
Full Idea: If suicide is allowed, then everything is allowed. If anything is not allowed, then suicide is not allowed. This throws a light on the nature of ethics, for suicide is, so to speak, the elementary sin. | |
From: Ludwig Wittgenstein (Notebooks 1914-1916 [1915], end), quoted by Jonathan Glover - Causing Death and Saving Lives §13 | |
A reaction: This reveals the religious streak in Wittgenstein. I am reluctant to judge suicide, but this seems wrong. Should a 'jumper' worry if they land on someone else and kill them? Of course they should. |
15093 | We might say laws are necessary by combining causal properties with Armstrong-Dretske-Tooley laws [Shoemaker] |
Full Idea: One way to get the conclusion that laws are necessary is to combine my view of properties with the view of Armstrong, Dretske and Tooley, that laws are, or assert, relations between properties. | |
From: Sydney Shoemaker (Causal and Metaphysical Necessity [1998], I) | |
A reaction: This is interesting, because Armstrong in particular wants the necessity to arise from relations between properties as universals, but if we define properties causally, and make them necessary, we might get the same result without universals. |