The man of science has learned to believe in justification, not by faith, but by verification.

“When I reached intellectual maturity, and began to ask myself whether I was an …”

“What we call rational grounds for our beliefs are often extremely irrational at…”

“The facts of variability, of the struggle for existence, of adaptation to condi…”

“Sit down before fact like a little child, and be prepared to give up every prec…”