18 ideas
| 8717 | Hilbert wanted to prove the consistency of all of mathematics (which realists take for granted) [Hilbert, by Friend] |
| Full Idea: Hilbert wanted to derive ideal mathematics from the secure, paradox-free, finite mathematics (known as 'Hilbert's Programme'). ...Note that for the realist consistency is not something we need to prove; it is a precondition of thought. | |
| From: report of David Hilbert (works [1900], 6.7) by Michčle Friend - Introducing the Philosophy of Mathematics | |
| A reaction: I am an intuitive realist, though I am not so sure about that on cautious reflection. Compare the claims that there are reasons or causes for everything. Reality cannot contain contradicitions (can it?). Contradictions would be our fault. |
| 10113 | The grounding of mathematics is 'in the beginning was the sign' [Hilbert] |
| Full Idea: The solid philosophical attitude that I think is required for the grounding of pure mathematics is this: In the beginning was the sign. | |
| From: David Hilbert (works [1900]), quoted by A.George / D.J.Velleman - Philosophies of Mathematics Ch.6 | |
| A reaction: Why did people invent those particular signs? Presumably they were meant to designate something, in the world or in our experience. |
| 10115 | Hilbert substituted a syntactic for a semantic account of consistency [Hilbert, by George/Velleman] |
| Full Idea: Hilbert replaced a semantic construal of inconsistency (that the theory entails a statement that is necessarily false) by a syntactic one (that the theory formally derives the statement (0 =1 ∧ 0 not-= 1). | |
| From: report of David Hilbert (works [1900]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.6 | |
| A reaction: Finding one particular clash will pinpoint the notion of inconsistency, but it doesn't seem to define what it means, since the concept has very wide application. |
| 10116 | Hilbert aimed to prove the consistency of mathematics finitely, to show infinities won't produce contradictions [Hilbert, by George/Velleman] |
| Full Idea: Hilbert's project was to establish the consistency of classical mathematics using just finitary means, to convince all parties that no contradictions will follow from employing the infinitary notions and reasoning. | |
| From: report of David Hilbert (works [1900]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.6 | |
| A reaction: This is the project which was badly torpedoed by Gödel's Second Incompleteness Theorem. |
| 2584 | Lobotomised patients can cease to care about a pain [Block] |
| Full Idea: After frontal lobotomies, patients typically report that they still have pains, though the pains no longer bother them. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 83) | |
| A reaction: I take this to be an endorsement of reductive physicalism, because what matters about pains is that they bother us, not how they feel, so frog pain could do the job, if it felt different from ours, but was disliked by the frog. |
| 2582 | A brain looks no more likely than anything else to cause qualia [Block] |
| Full Idea: NO physical mechanism seems very intuitively plausible as a seat of qualia, least of all a brain. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 78) | |
| A reaction: I'm not sure about "least of all", given the mind-boggling complexity of the brain's connections. Certainly, though, nothing in either folk physics or academic physics suggests that any physical object is likely to be aware of anything. |
| 2574 | Behaviour requires knowledge as well as dispositions [Block] |
| Full Idea: A desire cannot be identified with a disposition to act, since the agent might not know that a particular act leads to the thing desired, and thus might not be disposed to do it. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 69) | |
| A reaction: One might have a disposition to act, but not in a particular way. "Something must be done". To get to the particular act, it seems that indeed a belief must be added to the desire. |
| 2575 | Functionalism is behaviourism, but with mental states as intermediaries [Block] |
| Full Idea: Functionalism is a new incarnation of behaviourism, replacing sensory inputs with sensory inputs plus mental states, and replacing dispositions to act with dispositions plus certain mental states. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 69) | |
| A reaction: I think of functionalism as behaviourism which extends inside the 'black box' between stimulus and response. It proposes internal stimuli and responses. Consequently functionalism inherits some behaviourist problems. |
| 2583 | You might invert colours, but you can't invert beliefs [Block] |
| Full Idea: It is hard to see how to make sense of the analog of color spectrum inversion with respect to non-qualitative states such a beliefs (where they are functionally equivalent but have different beliefs). | |
| From: Ned Block (Troubles with Functionalism [1978], p. 81) | |
| A reaction: I would suggest that beliefs can be 'inverted', because there are all sorts of ways to implement a belief, but colour can't be inverted, because that depends on a particular brain state. It makes good sense to me... |
| 2576 | In functionalism, desires are internal states with causal relations [Block] |
| Full Idea: According to functionalism, a system might have the behaviouristic input-output relations, yet not desire something, as this requires internal states with certain causal relations. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 69) | |
| A reaction: Such a system might be Putnam's 'superactor', who only behaves as if he desires something. Of course, the internal states might need more than just 'causal relations'. |
| 2578 | Could a creature without a brain be in the right functional state for pain? [Block] |
| Full Idea: If pain is a functional state, it cannot be a brain state, because creatures without brains could realise the same Turing machine as creatures with brains. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 70) | |
| A reaction: This strikes me as being a poorly grounded claim. There may be some hypothetical world where brainless creatures implement all our functions, but from here brains look the only plausible option. |
| 2585 | Not just any old functional network will have mental states [Block] |
| Full Idea: If there are any fixed points in the mind-body problem, one of them is that the economy of Bolivia could not have mental states, no matter how it is distorted. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 86) | |
| A reaction: It is hard to disagree with this, but then it can hardly be a serious suggestion that anyone could see how to reconfigure an economy so that it mapped the functional state of the human brain. This is not a crucial problem. |
| 2586 | In functionalism, what are the special inputs and outputs of conscious creatures? [Block] |
| Full Idea: In functionalism, it is very hard to see how there could be a single physical characterization of the inputs and outputs of all and only creatures with mentality. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 87) | |
| A reaction: It would be theoretically possible if the only way to achieve mentality was to have a particular pattern of inputs and outputs. I don't think, though, that 'mentality' is an all-or-nothing concept. |
| 2579 | Physicalism is prejudiced in favour of our neurology, when other systems might have minds [Block] |
| Full Idea: Physicalism is a chauvinist theory: it withholds mental properties from systems that in fact have them. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 71) | |
| A reaction: This criticism interprets physicalism too rigidly. There may be several ways to implement a state. My own view is that other systems might implement our functions, but they won't experience them in a human way. |
| 2577 | Simple machine-functionalism says mind just is a Turing machine [Block] |
| Full Idea: In the simplest Turing-machine version of functionalism (Putnam 1967), mental states are identified with the total Turing-machine state, involving a machine table and its inputs and outputs. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 70) | |
| A reaction: This obviously invites the question of why mental states would be conscious and phenomenal, given that modern computers are devoid of same, despite being classy Turing machines. |
| 2580 | A Turing machine, given a state and input, specifies an output and the next state [Block] |
| Full Idea: In a Turing machine, given any state and input, the machine table specifies an output and the next state. …To have full power the tape must be infinite in at least one direction, and be movable in both directions. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 71) | |
| A reaction: In retrospect, the proposal that this feeble item should be taken as a model for the glorious complexity and richness of human consciousness doesn't look too plausible. |
| 2581 | Intuition may say that a complex sentence is ungrammatical, but linguistics can show that it is not [Block] |
| Full Idea: Linguistics rejects (on theoretical grounds) the intuition that the sentence "the boy the girl the cat bit scratched died" is ungrammatical. | |
| From: Ned Block (Troubles with Functionalism [1978], p. 78) | |
| A reaction: Once we have disentangled it, we practical speakers have no right to say it is ungrammatical. It isn't only theory. The sentence is just stylistically infelicitous. |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
| Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom. | |
| From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88) | |
| A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate'). |