Within the limits of nature's law, a man is free to mold his future. By design he may increase the probability of a desired outcome. And so we say that destiny is a choice, a selection among alternative destinies. But the selection cannot be left to accident; it is not fortuitous, automatic, foolproof. Man himself must choose.

The Advancing Front of Science - Epilogue (p. 353), Whittlesey House. 1937