Proust Was a Neuroscientist. Jonah Lehrer

* Shortly after breaking Eliot’s heart, Spencer wrote two cruel essays on “Personal Beauty” in which he extolled the virtues of prettiness. In his autobiography he had the audacity to brag of his shallowness, and wrote, in a veiled reference to Eliot, that “Physical beauty is a sine qua non with me; as was once unhappily proved where the intellectual traits and the emotional traits were of the highest.”

      But if Spencer was a man unable to see beyond appearances, Henry James believed Eliot was proof that personality could triumph over prettiness. James memorably described his first meeting with Eliot: “To begin with, she is magnificently ugly — deliciously hideous. She has a low forehead, a dull grey eye, a vast pendulous nose, a huge mouth full of uneven teeth and a chin and jaw bone qui n’en finessent [sic] pas … Now in this vast ugliness resides a most powerful beauty which, in a very few minutes steals forth and charms the mind, so that you end as I ended, in falling in love with her.”

* Necessitarianism is a synonym for determinism. Popular in the nineteenth century, the theory holds that human actions are “necessitated” by antecedent causes over which we have no control.

* Of course, being free also makes us accountable for our behavior. One of Eliot’s main problems with social physics was that it denied humanity any moral agency. After all, if every action has an external cause, then it seems cruel to punish cruelty. In her novels, Eliot wanted to describe a more realistic vision of human nature and thus inspire us to become better. If social physics made us callous, then art might make us compassionate.

* Darwin acknowledged the deep chanciness at the heart of natural selection. Although he never uses the adjective random, Darwin constantly asserts that variations are “undirected” and “occur in no determinate way.”

* Eliot enjoyed telling a story about her botanical expeditions to Kew Gardens with Spencer. Being a devout Darwinist, Spencer explained the structure of every flower by referencing some vague story about “the necessity of evolutionary development.” But if a flower failed to fit his neat theory, then it was “tant pis pour les fleurs” (“too bad for the flowers”).

* How did Rakic make his original mistake? There is no easy answer. Rakic is an excellent scientist, one of the finest neuroscientists of his generation. But seeing radioactive new neurons is extremely difficult. These cells are easy to ignore, especially if they shouldn’t be there. One has to be looking for them in order to see them. Furthermore, almost all lab primates live in an environment that suppresses neurogenesis. A drab-looking cage creates a drab-looking brain. Unless the primates are transferred to an enriched enclosure, their adult brains will produce few new neurons. The realization that typical laboratory conditions are debilitating for animals and produce false data has been one of the accidental discoveries of the neurogenesis field.

* Scientists are now discovering that even mental traits that have a strong genetic component — such as IQ — are incredibly sensitive to changes in the environment. A French study of troubled children adopted between the ages of four and six clearly demonstrated the way our innate human nature depends on how we are nurtured. At the time they were adopted, these young children had IQs that averaged around 77, putting them near retardation level. However, when the children retook the IQ test nine years later, all of them did significantly better. This was extremely surprising, since IQ is supposed to be essentially stable over the course of a lifetime. Furthermore, the amount that a child improved was directly related to the adopting family’s socioeconomic status. Children adopted by middle-class families had average scores of 92; those placed in upper-class homes had their IQs climb, on average, more than 20 points, to 98. In a relatively short time, their IQs had gone from significantly below average to practically normal.

* Although Kimura’s conclusions provoked a storm of controversy — some neo-Darwinists said he was just a creationist with fancy mathematics — they shouldn’t have. In fact, Darwin probably would have agreed with Kimura. In the last edition of On the Origin of Species, published in 1872, Darwin makes his own position crystal clear: “As my conclusions have lately been much misrepresented, and it has been stated that I attribute the modification of species exclusively to natural selection, I may be permitted to remark that in the first edition of this work, and subsequently, I placed in a most conspicuous position … the following words: ‘I am convinced that natural selection has been the main, but not the exclusive means of modification.’ This has been of no avail. Great is the power of steady misinterpretation” [Darwin, 1872, p. 395].