The study of nature is a perpetual joy.
对自然的研究是永恒的乐趣。
"To live is the rarest thing in the world. Most people exist, that is all."
The Worldly Hope men set their Hearts upon Turns Ashes—or it prospers; and anon, Like Snow upon the Desert's dusty Face, Lighting a little hour or two—is gone.
The environment shapes behavior through the mechanism of reinforcement.
The mathematician's best work is art, a high perfect art, as daring as the most secret dreams of imagination, clear and limpid.
