In the span of my own lifetime I observed such wondrous progress in plant evolution that I look forward optimistically to a healthy, happy world as soon as its children are taught the principles of simple and rational living.

For those who do not think, it is best at least to rearrange their prejudices once in a while.

It is well for people who think to change their minds occasionally in order to keep them clean. For those who do not think, it is best at least to rearrange their prejudices once in a while.

Heredity is nothing but stored environment.

If you violate Nature's laws you are your own prosecuting attorney, judge, jury, and hangman.