7 ideas
| 10845 | To be true a sentence must express a proposition, and not be ambiguous or vague or just expressive [Lewis] |
| Full Idea: Sentences or assertions can be derivately called true, if they succeed in expressing determinate propositions. A sentence can be ambiguous or vague or paradoxical or ungrounded or not declarative or a mere expression of feeling. | |
| From: David Lewis (Forget the 'correspondence theory of truth' [2001], p.276) | |
| A reaction: Lewis has, of course, a peculiar notion of what a proposition is - it's a set of possible worlds. I, with my more psychological approach, take a proposition to be a particular sort of brain event. |
| 10847 | Truthmakers are about existential grounding, not about truth [Lewis] |
| Full Idea: Instances of the truthmaker principle are equivalent to biconditionals not about truth but about the existential grounding of all manner of other things; the flying pigs, or what-have-you. | |
| From: David Lewis (Forget the 'correspondence theory of truth' [2001]) | |
| A reaction: The question then is what the difference is between 'existential grounding' and 'truth'. There wouldn't seem to be any difference at all if the proposition in question was a simple existential claim. |
| 10846 | Truthmaker is correspondence, but without the requirement to be one-to-one [Lewis] |
| Full Idea: The truthmaker principle seems to be a version of the correspondence theory of truth, but differs mostly in denying that the correspondence of truths to facts must be one-to-one. | |
| From: David Lewis (Forget the 'correspondence theory of truth' [2001], p.277) | |
| A reaction: In other words, several different sentences might have exactly the same truthmaker. |
| 19053 | Logic would be more natural if negation only referred to predicates [Dummett] |
| Full Idea: A better proposal for a formal logic closer to natural language would be one that had a negation-operator only for (simple) predicates. | |
| From: Michael Dummett (Presupposition [1960], p.27) | |
| A reaction: Dummett observes that classical formal logic was never intended to be close to natural language. Term logic does have that aim, but the meta-question is whether that end is desirable, and why. |
| 19052 | Natural language 'not' doesn't apply to sentences [Dummett] |
| Full Idea: Natural language does not possess a sentential negation-operator. | |
| From: Michael Dummett (Presupposition [1960], p.27) | |
| A reaction: This is a criticism of Strawson, who criticises logic for not following natural language, but does it himself with negation. In the question of how language and logic connect, this idea seems important. Term Logic aims to get closer to natural language. |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| Full Idea: Archelaus was the first person to say that the universe is boundless. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
| A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |