10 ideas
| 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? |
| 15789 | Lewis's distinction of 'existing' from 'being actual' is Meinong's between 'existing' and 'subsisting' [Lycan on Lewis] |
| Full Idea: I suggest that Lewis's view in fact is just Meinong's view. ...Meinong distinguishes between 'existing' and merely 'subsisting', Lewis between 'being actual' and merely 'existing'. | |
| From: comment on David Lewis (Possible Worlds [1973]) by William Lycan - The Trouble with Possible Worlds 06 | |
| A reaction: Lewis attempts to make actuality purely 'indexical' in character, like distinguishing the world 'here' from the world 'elsewhere', but Lycan seems right that he is committed to more than that. |
| 15790 | Lewis can't know possible worlds without first knowing what is possible or impossible [Lycan on Lewis] |
| Full Idea: Lewis's knowledge of what possible worlds there are and of other general truths about worlds is posterior, not prior, to his knowledge of what things are possible and what things are impossible. | |
| From: comment on David Lewis (Possible Worlds [1973]) by William Lycan - The Trouble with Possible Worlds 07 | |
| A reaction: This elementary objection seems to me to destroy any attempt to explain modality in terms of possible worlds. It is a semantics for modal statements, but that doesn't make it an ontology. To assess possibilities, study actuality. |
| 15791 | What are the ontological grounds for grouping possibilia into worlds? [Lycan on Lewis] |
| Full Idea: Lewis must seek some ontological ground for the grouping of possibilia into disjoint worlds. | |
| From: comment on David Lewis (Possible Worlds [1973]) by William Lycan - The Trouble with Possible Worlds 07 | |
| A reaction: I do love people like Lycan who ask the simple commonsense questions about these highly sophisticated systems that students of philosophy are required to study. If a proposition is a 'set of worlds', understanding a proposition is beyond me. |
| 14802 | Physical and psychical laws of mind are either independent, or derived in one or other direction [Peirce] |
| Full Idea: The question about minds is whether 1) physical and psychical laws are independent (monism, my neutralism), 2) the psychical laws derived and physical laws primordial (materialism), 3) physical law is derived, psychical law primordial (idealism). | |
| From: Charles Sanders Peirce (The Architecture of Theories [1891], p.321) | |
| A reaction: I think you are already in trouble when you start proposing that there are two quite distinct sets of laws, and then worry about how they are related. Assume unity, and only separate them when the science forces you to (which it won't). |
| 14800 | The world is full of variety, but laws seem to produce uniformity [Peirce] |
| Full Idea: Exact law obviously never can produce heterogeneity out of homogeneity; and arbitrary heterogeneity is the feature of the universe the most manifest and characteristic. | |
| From: Charles Sanders Peirce (The Architecture of Theories [1891], p.319) | |
| A reaction: This is the view of laws of nature now associated with Nancy Cartwright, but presumably you can explain the apparent chaos in terms of the intersection of vast numbers of 'laws'. Or, better, there aren't any laws. |
| 14801 | Darwinian evolution is chance, with the destruction of bad results [Peirce] |
| Full Idea: Darwinian evolution is evolution by the operation of chance, and the destruction of bad results. | |
| From: Charles Sanders Peirce (The Architecture of Theories [1891], p.320) | |
| A reaction: The 'destruction of bad results' is a much better slogan for Darwin that Spencer's 'survival of the fittest'. It is, of course, a rather unattractive God who makes progress by endlessly destroying huge quantities of failed (but living) experiments. |