Full Idea
Taking the principle of Excluded Middle away from the mathematician would be the same, say, as prohibiting the astronomer from using the telescope or the boxer from using his fists.
Gist of Idea
You would cripple mathematics if you denied Excluded Middle
Source
David Hilbert (The Foundations of Mathematics [1927], p.476), quoted by Ian Rumfitt - The Boundary Stones of Thought 9.4
Book Reference
Rumfitt,Ian: 'The Boundary Stones of Thought' [OUP 2015], p.285
A Reaction
[p.476 in Van Heijenoort]