William Safire on the history of the term animal spirits:

The phrase that Keynes made famous in economics has a long history. ‘‘Physitions teache that there ben thre kindes of spirites,’’ wrote Bartholomew Traheron in his 1543 translation of a text on surgery, ‘‘animal, vital, and naturall. The animal spirite hath his seate in the brayne called animal, bycause it is the first instrument of the soule, which the Latins call animam.’’

Novelists seized the expression’s upbeat sense with enthusiasm. Daniel Defoe, in ‘‘Robinson Crusoe’’: ‘‘That the surprise may not drive the Animal Spirits from the Heart.’’ Jane Austen used it to mean ‘‘ebullience’’ in ‘‘Pride and Prejudice’’: ‘‘She had high animal spirits.’’ Benjamin Disraeli, a novelist in 1844, used it in that sense: ‘‘He had great animal spirits, and a keen sense of enjoyment.’’ Feel better?

(hat tip: Thoma)

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