The onward flow of inventions may be interrupted, if not materially stayed, by the cessation of some of the causes and incentives which now give them life. 威廉·亨利·杜利特.世纪发明.
No other art was spurred to activity by such strong incentives, and none received the same encouragement and reward for its development. 威廉·亨利·杜利特.世纪发明.
Joy, mirth, vanity, and kindness are all incentives to this desire; as well as music, dancing, wine, and good cheer. 戴维·休谟.人性论.