|
9390
|
Logic guides thinking, but it isn't a substitute for it [Rumfitt]
|
|
Full Idea:
Logic is part of a normative theory of thinking, not a substitute for thinking.
|
|
From:
Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.13)
|
|
A reaction:
There is some sort of logicians' dream, going back to Leibniz, of a reasoning engine, which accepts propositions and outputs inferences. I agree with this idea. People who excel at logic are often, it seems to me, modest at philosophy.
|
|
9389
|
Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt]
|
|
Full Idea:
Vagueness in respect of membership is consistency with determinacy of the set's identity, so long as a set's identity is taken to consist, not in its having such-and-such members, but in its being the extension of a concept.
|
|
From:
Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.5)
|
|
A reaction:
I find this view of sets much more appealing than the one that identifies a set with its members. The empty set is less of a problem, as well as non-existents. Logicians prefer the extensional view because it is tidy.
|
|
16700
|
In order to speak about time and successive entities, the 'present' must be enlarged [Wycliff]
|
|
Full Idea:
It is clear from the way in which one must speak about time and other successive entities that talk about 'the present' must be enlarged. Otherwise it would have to be denied that any successive entity could exist, which is impossible.
|
|
From:
John Wycliff (De ente praedicamentali [1375], 20 p.189), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.3
|
|
A reaction:
This is a lovely idea, even if it is not quite clear what it means. The mind seems to stretch out the now anyway (as the 'specious present'), so why not embrace that in language and conscious thought?
|
|
16701
|
To be successive a thing needs parts, which must therefore be lodged outside that instant [Wycliff]
|
|
Full Idea:
If something is successive, it is successive with respect to its individual parts, which cannot exist at the same instant. Therefore it follows that many of its parts are lodged outside that instant.
|
|
From:
John Wycliff (De ente praedicamentali [1375], 20 p.189), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.3
|
|
A reaction:
An obvious would be to say that there are therefore no successive entities, but Wycliff is appealing to our universal acceptance of them, and offering a transcendental argument. Nice move.
|
|
23294
|
It is common to doubt truth when discussing it, but totally accept it when discussing knowledge [Davidson]
|
|
Full Idea:
You are following Plato's lead if you worry about the concept of truth when it is the focus of your attention, but you pretend you understand it when trying to cope with knowledge (or belief, memory, perception etc.).
|
|
From:
Donald Davidson (The Folly of Trying to Define Truth [1999], p.20)
|
|
A reaction:
Nice to find someone pointing out this absurdity. He says Hume does the same with doubts about the external world, which he ignores when discussing other minds. Belief is holding true; only truths are actually remembered….
|