Desire, to know why, and how, CURIOSITY; such as is in no living creature but Man; so that Man is distinguished, not only by his Reason; but also by this singular Passion from other Animals; in whom the appetite of food, and other pleasures of Sense, by predominance, take away the care of knowing causes; which is a Lust of the mind, that by a perseverance of delight in the continual and indefatigable generation of Knowledge, exceedeth the short vehemence of any carnal Pleasure.

The First Part, Chapter 6, p. 26. - Leviathan (1651)