Alfred Russel Wallace, Charles Darwin and the "evolution" of the human brain

University of California, Berkeley, USA

“I hope you have not murdered too completely your own and my child” — Charles Darwin to Alfred Russel Wallace, March 27, 1869.

In 1864 Wallace had written a paper on human evolution that received high praise from Darwin. Five years later, Wallace split from his co-discoverer of the theory of natural selection, over the evolution of the human brain, suggesting creation by a ‘Higher’ or ‘Overruling Intelligence’ and drawing the letter cited above. In a review of Lyell’s Principles of Geology, referring to “the mental requirements of the lowest savages,” Wallace argued that: “The higher moral faculties and those of pure intellect and refined emotion are useless to them.... How, then, was an organ developed so far beyond the needs of its possessor? Natural selection could only have endowed the savage with a brain a little superior to that of an ape, whereas he actually possesses one but very little inferior to that of the average members of our learned societies.”

Biographers attempting to grapple with Wallace’s apostasy, have generally been drawn toward his interest in spiritualism. That life-lasting commitment was genuine and is surely part of the story. But, there was also Wallace’s extreme “adaptationism.” As expressed, in a rarely-cited paper, “... no special organ, no characteristic form or marking, no peculiarities of instinct or of habit ... can exist but which must now be or once have been useful to the individuals or races which possess them.”

Finally, Wallace believed in Phrenology, sparked, in large part, by reading the works of George Combe. As an adaptationist / phrenologist, from his vantage point, Wallace had no choice but to defect: if an organ existed, in order to have been created by natural selection, “it must now be or once have been useful ...” Wallace’s citations of Ferrier and Hitzig, as justifying his early faith in Phrenology, will be discussed.

Session VII
Wednesday, 6 July 2005, 2.00 - 2.30 pm

Tenth Annual Meeting of the International Society for the History of the Neurosciences (ISHN) and
Tenth Meeting of the European Club for the History of Neurology (ECHN)

St. Andrews, Scotland, 2005