Michael S. Gazzaniga, Tales from Both Sides of the Brain: A Life in Neuroscience (2015)

This is a fun and informative read about a pioneering scientist who is also full of life. Gazzaniga made his mark by pioneering the study of split-brain patients, people who elected to have the corpus callosum - the major nerve pathway connecting the two brain hemispheres - cut in order to treat severe epilepsy (it worked). The initial shocking revelation was that the two hemispheres appeared to have minds of their own. As the years went by, as individual patients adapted to their new situation and as Gazzaniga and his team performed more experiments, it turned out that some communication between the brain-halves, even quite a bit, was possible after all. In some cases, this occurred when the cut was not complete and some nerve strands remained. More interesting, however, was the phenomenon of what Gazzaniga calls "cross-cueing." Namely, one hemisphere - say, the left, verbal one - might indirectly and unconsciously "cue" or hint to the other hemisphere what the left knew. Perhaps many brain functions work this way, Gazzaniga suggests, not just communication between the halves. Gazzaniga writes in a conversational, informal style. One very much senses the personality behind the prose. He enjoys life, he enjoys colleagues and people generally.

Joseph Henrich, The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter (2016)

An amazing book, certainly a leading candidate for my book of the year. I had read and greatly admired Henrich's more recent book, The WEIRDEST People in the World (2020). I knew that Henrich was a student (by now, clearly the leading student) of Robert Boyd and Peter Richerson, who since the 1980s have pioneered work on gene-culture coevolution. I haven't read Boyd and Richerson's works (for example, Culture and the Evolutionary Process [1985] or Not By Genes Alone [2005]) in quite a few years, so I can't say precisely how Henrich builds on, and perhaps modifies, their approach. Henrich makes a persuasive case that cultural evolution - learning ideas, techniques, facts and values from others - has become the dominant force shaping human genetic evolution over roughly the last two million years. Just to give one among Henrich's innumerable fascinating examples, one of early humans' early advantages was that we became excellent pursuit hunters. Even though we weren't faster or stronger than most animals, we became able to track animal spoor and, over hours, run our prey into exhaustion. In order to become excellent long-distance runners, our legs had to become longer and we had to develop the ability to sweat over much of our bodies. However, certain skills and technologies were also required, such as the ability to follow the tracks of particular individual animals, and the ability to carry water with us or extract it from the ground. These skills and technologies, Henrich shows, could never have been developed by individuals or even by groups - they had to evolve culturally, over generations. A key concept for Henrich is cumulative cultural evolution - culture (technologies, say) build on previous culture. Henrich has command of a wide range of literatures, showing how multiple streams of evidence support his case. As I said, I can't say exactly how his argument compares to Boyd and Richerson's, but I think he puts cultural evolution even more in the driver's seat than they did. As he says, he's proposing a new science of "a new kind of animal," one that draws on a collective brain to solve problems. Citing John Maynard Smith and Eors Szathmary's work on major transitions in evolution, Henrich suggests humans now find themselves in just such a transition to super-organisms. On a smaller scale, I learned fascinating things about "faith," i.e. trust in cultural processes that are smarter than any individual's intelligence; humans' two systems of status hierarchy - the dominance hierarchy we've inherited from our great ape forebears, and a newer prestige hierarchy; how our perception of "races" (sometimes mistakenly) draws on our "ethnic" psychology, which uses cues such as dialect and clothing to determine if somebody likely shares our norms; the close ties between tool making and language; etc. This short, and hastily written, comment doesn't do justice to this landmark book.

J. Bradford DeLong, Slouching Towards Utopia: An Economic History of the Twentieth Century (2022)

While this was a fun read, it was ultimately a disappointing book. DeLong, an economist at Berkeley, is very smart (and knows it) and widely read. He writes in a very conversational way and, in the acknowledgements, even thanks the Committee on Degrees in Social Studies at Harvard, his undergraduate major (and where I developed a love of teaching 20 years after DeLong was a student there) - a rare acknowledgement by an established scholar. I learned quite a bit from the book and jotted down quite a few notes. But DeLong's reputation as a brilliant thinker, the blog posts of his which I've read, and the intriguing title led me to expect a tour de force. Instead, his arguments are often too informal - his account, for example, of why the near-utopia under the Bretton Woods system ended amounts to a listing - not even a weighing - of familiar culprits. Perhaps more fundamentally, his focus is on material well-being (economic output and standards of living) - understandably, for an ecobomist. But while he briefly acknowledges that material well-being is insufficient to human flourishing, he never explores the other elements - for example, the kinds of social relations and communities people live in; the role of rising expectations and positional, zero-sum competition.