9358
|
There are several logics, none of which will ever derive falsehoods from truth [Lewis,CI]
|
|
Full Idea:
The fact is that there are several logics, markedly different, each self-consistent in its own terms and such that whoever, using it, avoids false premises, will never reach a false conclusion.
|
|
From:
C.I. Lewis (A Pragmatic Conception of the A Priori [1923], p.366)
|
|
A reaction:
As the man who invented modal logic in five different versions, he speaks with some authority. Logicians now debate which version is the best, so how could that be decided? You could avoid false conclusions by never reasoning at all.
|
9357
|
Excluded middle is just our preference for a simplified dichotomy in experience [Lewis,CI]
|
|
Full Idea:
The law of excluded middle formulates our decision that whatever is not designated by a certain term shall be designated by its negative. It declares our purpose to make a complete dichotomy of experience, ..which is only our penchant for simplicity.
|
|
From:
C.I. Lewis (A Pragmatic Conception of the A Priori [1923], p.365)
|
|
A reaction:
I find this view quite appealing. 'Look, it's either F or it isn't!' is a dogmatic attitude which irritates a lot of people, and appears to be dispensible. Intuitionists in mathematics dispense with the principle, and vagueness threatens it.
|
19406
|
I strongly believe in the actual infinite, which indicates the perfections of its author [Leibniz]
|
|
Full Idea:
I am so much for the actual infinite that instead of admitting that nature abhors it, as is commonly said, I hold that it affects nature everywhere in order to indicate the perfections of its author.
|
|
From:
Gottfried Leibniz (Reply to Foucher [1693], p.99)
|
|
A reaction:
I would have thought that, for Leibniz, while infinities indicate the perfections of their author, that is not the reason why they exist. God wasn't, presumably, showing off. Leibniz does not think we can actually know these infinities.
|
9365
|
We can maintain a priori principles come what may, but we can also change them [Lewis,CI]
|
|
Full Idea:
The a priori contains principles which can be maintained in the face of all experience, representing the initiative of the mind. But they are subject to alteration on pragmatic grounds, if expanding experience shows their intellectual infelicity.
|
|
From:
C.I. Lewis (A Pragmatic Conception of the A Priori [1923], p.373)
|
|
A reaction:
[compressed] This simply IS Quine's famous 'web of belief' picture, showing how firmly Quine is in the pragmatist tradition. Lewis treats a priori principles as a pragmatic toolkit, which can be refined to be more effective. Not implausible...
|
9363
|
Science seeks classification which will discover laws, essences, and predictions [Lewis,CI]
|
|
Full Idea:
The scientific search is for such classification as will make it possible to correlate appearance and behaviour, to discover law, to penetrate to the "essential nature" of things in order that behaviour may become predictable.
|
|
From:
C.I. Lewis (A Pragmatic Conception of the A Priori [1923], p.368)
|
|
A reaction:
Modern scientific essentialists no longer invoke scare quotes, and I think we should talk of the search for the 'mechanisms' which explain behaviour, but Lewis seems to have been sixty years ahead of his time.
|