“Was Euclid mad?” she asked, quite seriously.
There was something in the nature of a ricochet in that question. It touched not only Euclid, for whom we have infinite respect, but also ourselves, for whom we have more.
“The sanest person that ever lived,” said Cruikshank, shortly.
“Then why did he waste his time inventing all that rubbish? What’s the good of it, anyhow?”
I put away my pencil with which from memory I had just been drawing the diagram for the fourth proposition of the second book.
“It develops,” I answered, “the reasoning power in the human animal—a not unworthy or wholly unnecessary purpose.”
She darned a few stitches in silence.
“Has it ever done any good besides that?” she inquired presently.
“Well,” said Cruikshank, “it teaches you, for example, how, without measuring and purely by the light of reason, to construct an equilateral triangle on a given finite straight line.”