The Expression of the Emotions in Man and Animals the issues at play, writing: "The force of language is much aided by the expressive movements of the face and body" - hinting at a neurological intimacy of language with psychomotor function (body language),and underscoring the social value of expression. Darwin's Sources on Emotional Expression: Darwin had listened to a discussion about emotional expression at the Plinian Society in December 1826 when he was a medical student at Edinburgh University. This had been prompted by the publication of Sir Charles Bell's "Anatomy and Philosophy of Expression"; and in his presentation, the phrenologist William A.F. Browne (in a spirited account of
The Expression of the Emotions in Man and Animals with engravings of the Darwin family's domestic pets by the zoological illustrator T. W. Wood as well as work by the artists Briton Rivière, Joseph Wolf and A.D. May. It also included portraits by the Swedish photographer Oscar Rejlander (1813–1875), anatomical diagrams by Sir Charles Bell (1774–1842) and Friedrich Henle (1809–1885), as well as illustrational quotations from the "Mécanisme de la physionomie humaine" (1862) by the French neurologist Duchenne de Boulogne (1806–1875). As a result of his domestic psychology experiments, Darwin reduced the number of commonly observed emotions from Duchenne's calculation of more than sixty facial expressions, to just six