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.
Gist of Idea
Excluded middle is just our preference for a simplified dichotomy in experience
Source
C.I. Lewis (A Pragmatic Conception of the A Priori [1923], p.365)
Book Reference
Peirce,James,Dewey etc: 'Pragmatism - The Classic Writings', ed/tr. Thayer,H.S. [Hackett 1982], 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.