This is the fourth of John Brockman's books that I have read and reviewed, and I think the best. Previously Brockman asked scientists, What do you believe but cannot prove?, What's your dangerous idea?, and What are you optimistic about? Here he asks scientist the title question, What have you changed your mind about? I think this question energized the 150 respondents and made the responses most interesting.
What Princeton Professor Lee M. Silver has changed his mind about is the effectiveness of modern education to get humans to reject supernatural beliefs or "to accept scientific implications of rational argumentation." What he has discovered over the years is that "irrationality and mysticism seem to be an integral part of normal human nature." (pp. 144-146)
Well, I've noticed the same thing and so have a lot of other people. The question is why should our minds be in such a sorry state? The broad answer is evolution made them that way because that was what worked.
Irrationality works? Strange to say, but sometimes it does--or has. Since even the most rational of our prehistoric ancestors could not know when the tsunami was coming or how to avoid drought and disease, rational thinking had a limited applicability. In some cases more value was to be found in certain rituals and mumbled words that gave our ancestors heart and allowed them to avoid despair.
The problem with this is that in the modern world, with the power of science and our knowledge of history to guide us, we would be much better off if we were able to throw off the irrationality and work together toward logical and informed solutions to our problems.
Cosmologist and President of the Royal Society, Martin Rees used to believe that the fairly distant future ought to be "best left to speculative academics and cosmologists." Now, with rapid acceleration in cultural evolution that we are experiencing, he feels that "We are custodians of a 'posthuman future'--here on Earth and perhaps beyond--that cannot just be left to writers of science fiction." (pp. 29-31)
Laurence C. Smith, Professor of Geology at UCLA used to think that the effects of global warming would be gradual, but now he believes that such effects, both positive and negative" may already be upon us." He cites the rapidity with which the Arctic Ocean is becoming ice-free for changing his mind. He notes that "Over the past three years, experts have shifted from 2050 to 2035 to 2013 as plausible dates for an ice-free Arctic Ocean..." "Reality," it appears, is revising the models. (pp. 141-143)
J. Craig Venter, human genome decoder, used to believe that "solving the carbon-fuel problem was for future generations and that the big concern was the limited supply of oil, not the rate of adding carbon to the atmosphere." Now he believes greenhouse gas emissions could result in "catastrophic changes" more quickly that previously imagined, and that "we are conducting a dangerous experiment with our planet. One that we need to stop." (pp. 139-140)
Physicist Lee Smolin has changed his mind about time. Originally he believed that (quantum) reality is timeless. Then he came to believe that "time, as causality, is real." Now he writes, "Rather than being an illusion, time may be the only aspect of our present understanding of nature that is not temporary and emergent." (pp. 148-149)
I am not sure what kind of distinction Smolin is making between a reality that is timeless and one in which time is causality. I think that in both instances time does not exist and is, as Smolin reports," an illusion" that some philosophers and physicists believe "is just an 'emergent quantity' that is helpful in organizing our observations..." (p. 147)
What I think would be helpful is to realize that causality is the ordering of events with no concept of "time" needed. We say that event A occurred "before" event B as though having reference to "time," but this is just a verbalism. Notice that we also say that the numeral 2 appears "before" the numeral 3 or "after" the numeral 1 in an ordering. Again time is not involved.
Physicist Lawrence Krauss used to believe that the universe was flat. Now he thinks it will go on expanding forever. (pp. 159-161)
Richard Wrangham, author of excellent "Demonic Males: Apes and the Origins of Human Violence," now believes it was cooking that transformed us from Homo habilis through Homo erectus to Homo sapiens and not meat-eating. He now believes that erectus used fire although clear proof is still lacking. (pp. 242-244)
Steve Connor, Science Editor of The Independent, now sees the 21st century bringing horrors worse than the Holocaust and nuclear proliferation. The culprits? "[G]lobal warming and the inexorable growth in the human population" leading to a stampede by the four horsemen of the apocalypse. He believes that the IPCC is underestimating the pace and extent of global warming. (pp. 327-330)
Richard Dawkins has changed his mind about Amotz Zahavi's "handicap principle" in evolutionary biology. (pp. 335-338) Dawkins's change of heart seems somewhat reluctant however and is, judging by the entry in this book, applicable to only the sexual selection aspect of the handicap principle. Dawkins allows that yes, superior male animals like the peacock may take on the handicap of appendages or behaviors that put them in increased danger just so they can "say" to the opposite sex: "See how fit I am. I can carry around his otherwise useless and heavy tail and still make a good living. Reproduce with me!"
But Dawkins does not mention the predator-prey aspect of Zahavi's handicap principle, such as the springbok pronking (jumping up and down conspicuously) to demonstrate to predators its fitness, "saying,": "Don't waste your energy chasing me. I am too fit for you to catch."
What I would like to see Dawkins change his mind about is group selection. He has allowed that group selection may be a (small) factor in evolution in some instances. What he needs to acknowledge is that selection occurs at various levels from the gene on up.
There is much, much more in this fascinating book. Don't miss it.