9 ideas
| 11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
| Full Idea: If a designated conclusion follows from the premisses, but the argument involves two howlers which cancel each other out, then the moral is that the path an argument takes from premisses to conclusion does matter to its logical evaluation. | |
| From: Ian Rumfitt ("Yes" and "No" [2000], II) | |
| A reaction: The drift of this is that our view of logic should be a little closer to the reasoning of ordinary language, and we should rely a little less on purely formal accounts. |
| 11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
| Full Idea: If 'and' and 'but' really are alike in sense, in what might that likeness consist? Some philosophers of classical logic will reply that they share a sense by virtue of sharing a truth table. | |
| From: Ian Rumfitt ("Yes" and "No" [2000]) | |
| A reaction: This is the standard view which Rumfitt sets out to challenge. |
| 11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
| Full Idea: A connective will possess the sense that it has by virtue of its competent users' finding certain rules of inference involving it to be primitively obvious. | |
| From: Ian Rumfitt ("Yes" and "No" [2000], III) | |
| A reaction: Rumfitt cites Peacocke as endorsing this view, which characterises the logical connectives by their rules of usage rather than by their pure semantic value. |
| 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). |
| 18052 | An assertion aims to add to the content of a context [Stalnaker, by Magidor] |
| Full Idea: Stalnaker starts with the general thesis that the role of a successful assertion of s is to update the context by adding to it the content of s. | |
| From: report of Robert C. Stalnaker (Assertion [1978]) by Ofra Magidor - Category Mistakes 5.3.2 | |
| A reaction: This is to be compared with criteria of meaningfulness, such as verificationism, and with Grice's rules of conversational implicature. Presumably if you assert what the context presupposes, you fail to assert, without being meaningless. |
| 11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |
| Full Idea: The standard view is that affirming not-A is more complex than affirming the atomic sentence A itself, with the latter determining its sense. But we could learn 'not' directly, by learning at once how to either affirm A or reject A. | |
| From: Ian Rumfitt ("Yes" and "No" [2000], IV) | |
| A reaction: [compressed] This seems fairly anti-Fregean in spirit, because it looks at the psychology of how we learn 'not' as a way of clarifying what we mean by it, rather than just looking at its logical behaviour (and thus giving it a secondary role). |
| 14718 | An assertion is an attempt to rule out certain possibilities, narrowing things down for good planning [Stalnaker, by Schroeter] |
| Full Idea: Stalnaker's guiding idea is that in making an assertion the speaker is trying to get the audience to rule out certain possibilities. ....If all goes well, further planning will proceed on the basis of a smaller and more accurate range of possibilities. | |
| From: report of Robert C. Stalnaker (Assertion [1978]) by Laura Schroeter - Two-Dimensional Semantics | |
| A reaction: This sounds intuitively rather plausible, and is a nice original thought. This is what we pay clever chaps like Stalnaker to come up with. It seems to imply some notion of verisimilitude (qv. under 'truth'), depending on how much narrowing happens. |
| 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. |