display all the ideas for this combination of texts
2 ideas
18168 | 'Propositional functions' are propositions with a variable as subject or predicate [Maddy] |
Full Idea: A 'propositional function' is generated when one of the terms of the proposition is replaced by a variable, as in 'x is wise' or 'Socrates'. | |
From: Penelope Maddy (Naturalism in Mathematics [1997], I.1) | |
A reaction: This implies that you can only have a propositional function if it is derived from a complete proposition. Note that the variable can be in either subject or in predicate position. It extends Frege's account of a concept as 'x is F'. |
11175 | Logical concepts rest on certain inferences, not on facts about implications [Fine,K] |
Full Idea: The nature of the logical concepts is given, not by certain logical truths, but by certain logical inferences. What properly belongs to disjunction is the inference from p to (p or q), rather than the fact that p implies (p or q). | |
From: Kit Fine (Senses of Essence [1995], §3) | |
A reaction: Does this mean that Fine is wickedly starting with the psychology, rather than with the pure truth of the connection? Frege is shuddering. This view seems to imply that the truth table for 'or' is secondary. |