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All the ideas for 'The Runabout Inference Ticket', 'Mental Models' and 'Papers of 1913'

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6 ideas

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
17896 We need to know the meaning of 'and', prior to its role in reasoning [Prior,AN, by Belnap]
     Full Idea: For Prior, so the moral goes, we must first have a notion of what 'and' means, independently of the role it plays as premise and as conclusion.
     From: report of Arthur N. Prior (The Runabout Inference Ticket [1960]) by Nuel D. Belnap - Tonk, Plonk and Plink p.132
     A reaction: The meaning would be given by the truth tables (the truth-conditions), whereas the role would be given by the natural deduction introduction and elimination rules. This seems to be the basic debate about logical connectives.
17898 Prior's 'tonk' is inconsistent, since it allows the non-conservative inference A |- B [Belnap on Prior,AN]
     Full Idea: Prior's definition of 'tonk' is inconsistent. It gives us an extension of our original characterisation of deducibility which is not conservative, since in the extension (but not the original) we have, for arbitrary A and B, A |- B.
     From: comment on Arthur N. Prior (The Runabout Inference Ticket [1960]) by Nuel D. Belnap - Tonk, Plonk and Plink p.135
     A reaction: Belnap's idea is that connectives don't just rest on their rules, but also on the going concern of normal deduction.
11021 Prior rejected accounts of logical connectives by inference pattern, with 'tonk' his absurd example [Prior,AN, by Read]
     Full Idea: Prior dislike the holism inherent in the claim that the meaning of a logical connective was determined by the inference patterns into which it validly fitted. ...His notorious example of 'tonk' (A → A-tonk-B → B) was a reductio of the view.
     From: report of Arthur N. Prior (The Runabout Inference Ticket [1960]) by Stephen Read - Thinking About Logic Ch.8
     A reaction: [The view being attacked was attributed to Gentzen]
13836 Maybe introducing or defining logical connectives by rules of inference leads to absurdity [Prior,AN, by Hacking]
     Full Idea: Prior intended 'tonk' (a connective which leads to absurdity) as a criticism of the very idea of introducing or defining logical connectives by rules of inference.
     From: report of Arthur N. Prior (The Runabout Inference Ticket [1960], §09) by Ian Hacking - What is Logic?
10. Modality / B. Possibility / 1. Possibility
22308 Only the actual exists, so possibilities always reduce to actuality after full analysis [Russell]
     Full Idea: Possibility always marks insufficient analysis: when analysis is completed, only the actual can be relevant, for the simple reason that there is only the actual, and that the mere possibility is nothing.
     From: Bertrand Russell (Papers of 1913 [1913], VII.26), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 42 'Logic'
     A reaction: Quine agreed with Russell on this. You won't get far in life if you deny possibilities. The answer is to recognise that the actual is dynamic, and not passive.
14. Science / B. Scientific Theories / 7. Scientific Models
3214 The models we use in reasoning may be more like perceptions than like language [Johnson-Laird]
     Full Idea: The models that people use to reason are more likely to resemble perception or conception of the events (from a God's-eye view) than a string of symbols directly corresponding to the linguistic form of the premises and then applying rules of inference.
     From: P. Johnson-Laird (Mental Models [1983], p.53), quoted by Georges Rey - Contemporary Philosophy of Mind 10.1.2
     A reaction: My intuition is that imagination is the single most important faculty in any conscious mind, and that even small animals have an inkling of the God's-eye view. Decisions need 'what-if' scenarios.