20 ideas
2626 | A philosopher is outside any community of ideas [Wittgenstein] |
Full Idea: The philosopher is not a citizen of any community of ideas; that is what makes him a philosopher. | |
From: Ludwig Wittgenstein (Zettel [1950], 455) | |
A reaction: A bit surprising from the man who gave us 'language games' and 'private language argument'. |
4465 | Note that "is" can assert existence, or predication, or identity, or classification [PG] |
Full Idea: There are four uses of the word "is" in English: as existence ('he is at home'), as predication ('he is tall'), as identity ('he is the man I saw'), and as classification ('he is British'). | |
From: PG (Db (ideas) [2031]) | |
A reaction: This seems a nice instance of the sort of point made by analytical philosophy, which can lead to horrible confusion in other breeds of philosophy when it is overlooked. |
4686 | Fallacies are errors in reasoning, 'formal' if a clear rule is breached, and 'informal' if more general [PG] |
Full Idea: Fallacies are errors in reasoning, labelled as 'formal' if a clear rule has been breached, and 'informal' if some less precise error has been made. | |
From: PG (Db (ideas) [2031]) | |
A reaction: Presumably there can be a grey area between the two. |
7415 | Question-begging assumes the proposition which is being challenged [PG] |
Full Idea: To beg the question is to take for granted in your argument that very proposition which is being challenged | |
From: PG (Db (ideas) [2031]) | |
A reaction: An undoubted fallacy, and a simple failure to engage in the rational enterprise. I suppose one might give a reason for something, under the mistaken apprehension that it didn't beg the question; analysis of logical form is then needed. |
7414 | What is true of a set is also true of its members [PG] |
Full Idea: The fallacy of division is the claim that what is true of a set must therefore be true of its members. | |
From: PG (Db (ideas) [2031]) | |
A reaction: Clearly a fallacy, but if you only accept sets which are rational, then there is always a reason why a particular is a member of a set, and you can infer facts about particulars from the nature of the set |
6696 | The Ad Hominem Fallacy criticises the speaker rather than the argument [PG] |
Full Idea: The Ad Hominem Fallacy is to criticise the person proposing an argument rather than the argument itself, as when you say "You would say that", or "Your behaviour contradicts what you just said". | |
From: PG (Db (ideas) [2031]) | |
A reaction: Nietzsche is very keen on ad hominem arguments, and cheerfully insults great philosophers, but then he doesn't believe there is such a thing as 'pure argument', and he is a relativist. |
4687 | Minimal theories of truth avoid ontological commitment to such things as 'facts' or 'reality' [PG] |
Full Idea: Minimalist theories of truth are those which involve minimum ontological commitment, avoiding references to 'reality' or 'facts' or 'what works', preferring to refer to formal relationships within language. | |
From: PG (Db (ideas) [2031]) | |
A reaction: Personally I am suspicious of minimal theories, which seem to be designed by and for anti-realists. They seem too focused on language, when animals can obviously formulate correct propositions. I'm quite happy with the 'facts', even if that is vague. |
6516 | Monty Hall Dilemma: do you abandon your preference after Monty eliminates one of the rivals? [PG] |
Full Idea: The Monty Hall Dilemma: Three boxes, one with a big prize; pick one to open. Monty Hall then opens one of the other two, which is empty. You may, if you wish, switch from your box to the other unopened box. Should you? | |
From: PG (Db (ideas) [2031]) | |
A reaction: The other two boxes, as a pair, are more likely contain the prize than your box. Monty Hall has eliminated one of them for you, so you should choose the other one. Your intuition that the two remaining boxes are equal is incorrect! |
6569 | 'This sentence is false' sends us in a looping search for its proposition [Wittgenstein, by Fogelin] |
Full Idea: According to Wittgenstein, 'this sentence is false' sends us off on an endless, looping search for the proposition to be evaluated. | |
From: report of Ludwig Wittgenstein (Zettel [1950], §691) by Robert Fogelin - Walking the Tightrope of Reason Ch.2 | |
A reaction: Fogelin quotes this as one possible strategy for dealing with the Liar Paradox. It doesn't sound like much of a solution to the paradox, merely an account of why it is so annoying. Wittgenstein's challenge is that the Cretan can't state his problem. |
14963 | Surely the past phases of a thing are not parts of the thing? [Broad] |
Full Idea: It is plainly contrary to common sense to say that the phases in the history of a thing are parts of the thing. | |
From: C.D. Broad (Examination of McTaggart's Philosophy [1933], I.349-50), quoted by Richard Cartwright - Scattered Objects n18 | |
A reaction: Nicely expressed! To suggest that me ten years ago is a mere part of some huge me, or that you are only talking to a part of me now, is a very long way indeed from normal usage. |
24054 | Everything has a probability, something will happen, and probabilities add up [PG] |
Full Idea: The three Kolgorov axioms of probability: the probability of an event is a non-negative real number; it is certain that one of the 'elementary events' will occur; and the unity of probabilities is the sum of probability of parts ('additivity'). | |
From: PG (Db (ideas) [2031]) | |
A reaction: [My attempt to verbalise them; they are normally expressed in terms of set theory]. Got this from a talk handout, and Wikipedia. |
3875 | If reality is just what we perceive, we would have no need for a sixth sense [PG] |
Full Idea: Reality must be more than merely what we perceive, because a sixth sense would enhance our current knowledge, and a seventh, and so on. | |
From: PG (Db (ideas) [2031]) |
3876 | If my team is losing 3-1, I have synthetic a priori knowledge that they need two goals for a draw [PG] |
Full Idea: If my football team is losing 3-1, I seem to have synthetic a priori knowledge that they need two goals to achieve a draw | |
From: PG (Db (ideas) [2031]) |
3790 | Causes of beliefs are irrelevant to their contents [Wittgenstein] |
Full Idea: The causes of our belief in a proposition are indeed irrelevant to the question of what we believe. | |
From: Ludwig Wittgenstein (Zettel [1950], i.437) | |
A reaction: This should have nipped the causal theory of knowledge in the bud before it got started. Everyone has a different cause for their belief that 'it sometimes rains'. Cause is not justification. |
7734 | Maybe a mollusc's brain events for pain ARE of the same type (broadly) as a human's [PG] |
Full Idea: To defend type-type identity against the multiple realisability objection, we might say that a molluscs's brain events that register pain ARE of the same type as humans, given that being 'of the same type' is a fairly flexible concept. | |
From: PG (Db (ideas) [2031]) | |
A reaction: But this reduces 'of the same type' to such vagueness that it may become vacuous. You would be left with token-token identity, where the mental event is just identical to some brain event, with its 'type' being irrelevant. |
7735 | Maybe a frog's brain events for fear are functionally like ours, but not phenomenally [PG] |
Full Idea: To defend type-type identity against the multiple realisability objection, we might (also) say that while a frog's brain events for fear are functionally identical to a human's (it runs away), that doesn't mean they are phenomenally identical. | |
From: PG (Db (ideas) [2031]) | |
A reaction: I take this to be the key reply to the multiple realisability problem. If a frog flees from a loud noise, it is 'frightened' in a functional sense, but that still leaves the question 'What's it like to be a frightened frog?', which may differ from humans. |
3877 | Utilitarianism seems to justify the discreet murder of unhappy people [PG] |
Full Idea: If I discreetly murdered a gloomy and solitary tramp who was upsetting people in my village, if is hard to see how utilitarianism could demonstrate that I had done something wrong. | |
From: PG (Db (ideas) [2031]) |
6126 | Life is Movement, Respiration, Sensation, Nutrition, Excretion, Reproduction, Growth (MRS NERG) [PG] |
Full Idea: The biologists' acronym for the necessary conditions of life is MRS NERG: that is, Movement, Respiration, Sensation, Nutrition, Excretion, Reproduction, Growth. | |
From: PG (Db (ideas) [2031]) | |
A reaction: How strictly necessary are each of these is a point for discussion. A notorious problem case is fire, which (at a stretch) may pass all seven tests. |
3873 | An omniscient being couldn't know it was omniscient, as that requires information from beyond its scope of knowledge [PG] |
Full Idea: God seems to be in the paradoxical situation that He may be omniscient, but can never know that He is, because that involves knowing that there is nothing outside his scope of knowledge (e.g. another God) | |
From: PG (Db (ideas) [2031]) |
3874 | How could God know there wasn't an unknown force controlling his 'free' will? [PG] |
Full Idea: How could God be certain that he has free will (if He has), if He couldn't be sure that there wasn't an unknown force controlling his will? | |
From: PG (Db (ideas) [2031]) |