Common sense, immersed in the mere business of living, knows no more
about life than a fish knows about water. The play of reason upon
phenomena dissects life, and translates it in terms of inertia. The
pure logic of mathematics ignores life and disdains its limitations,
leading away into cold, free regions of its own. Now our desire for
freedom is not to vibrate in a vacuum, but to live more abundantly.
_Intuition_ deals with life directly, and introduces us into
life's own domain: it is related to reason as flame is related to
heat. All of the great discoveries in science, all of the great
solutions in mathematics, have been the result of a _flash_ of
intuition, after long brooding in the mind. _Intuition illumines_.
Intuition is therefore the light which must guide us into that
undiscovered country conceded by mathematics, questioned by science,
denied by common sense--_The Fourth Dimension of Space_.