I have two perspectives on what this might mean,’’ he said. “One says: humans are like rats or cockroaches. We are already living from the equator to the Arctic Circle. The weather has already become .7 degrees warmer, and barely anyone has noticed or cares. And, yes, the coral reefs might become extinct, and people from the Seychelles might go hungry. But they have gone hungry in the past, and nobody cared. So basically we will live in our gated communities, and we will have our TV shows and Chicken McNuggets, and we will be O.K. The people who would suffer are the people who always suffer. “There is another way to look at this, though,’’ he said. “And that is to compare it to the subprime-mortgage crisis, where you saw that a few million bad mortgages led to a five-per-cent drop in gross domestic product throughout the world. Something that was a relatively small knock to the financial system led to a global crisis. And that could certainly be the case with climate change. But five per cent is an interesting figure, because in the Stern Report’’—an often cited review led by the British economist Nicholas Stern, which signalled the alarm about greenhouse-gas emissions by focussing on economics—“they estimated climate change would cost the world five per cent of its G.D.P. Most economists say that solving this problem is one or two per cent of G.D.P. The Clean Water and Clean Air Acts each cost about one per cent of G.D.P.,” Caldeira continued. “We just had a much worse shock to our banking system. And it didn’t even get us to reform the economy in any significant way. So why is the threat of a five-per-cent hit from climate change going to get us to transform the energy system?

Liston operated so fast that he once accidentally amputated an assistant’s fingers along with a patient’s leg, according to Hollingham. The patient and the assistant both died of sepsis, and a spectator reportedly died of shock, resulting in the only known procedure with a 300% mortality.

Krauss also has a naively optimistic view of the business of science, as it turns out. For instance, he claims that “the difference [between scientists and philosophers] is that scientists are really happy when they get it wrong, because it means that there’s more to learn.” Seriously? I’ve practiced science for more than two decades, and I’ve never seen anyone happy to be shown wrong, or who didn’t react as defensively (or even offensively) as possible to any claim that he might be wrong. Indeed, as physicist Max Plank famously put it, “Science progresses funeral by funeral,” because often the old generation has to retire and die before new ideas really take hold. Lawrence, scientists are just human beings, and like all human beings they are interested in mundane things like sex, fame and money (and yes, the pursuit of knowledge). Science is a wonderful and wonderfully successful activity (despite the more than occasional blunder), but there is no reason to try to make its practitioners look like some sort of intellectual saints that they certainly are not (witness also the alarming increase in science fraud, for instance).

The knowledge of sin is the beginning of salvation.” This saying of Epicurus/a seems to me to be a noble one. For he who does not know that he has sinned does not desire correction; you must discover yourself in the wrong before you can reform yourself. Some boast of their faults. Do you think that the man has any thought of mending his ways who counts over his vices as if they were virtues? Therefore, as far as possible, prove yourself guilty, hunt up charges against yourself; play the part, first of accuser, then of judge, last of intercessor. At times be harsh with yourself.

The person you are matters more than the place to which you go; for that reason we should not make the mind a bondsman to any one place. Live in this belief: “I am not born for any one corner of the universe; this whole world is my country.

I asked some people at work if they “take movies seriously as mainstream entertainment.” They weren’t sure what I was asking. The best answer I got was, “Uh, I watch movies all the time.” Perfect. I think at some point, gamers would love that question to be as nonsensical to people, only with the word “games” in there.

Back to the debate over evolution: partisans such as those supporting the Tennessee bill have gotten a lot of mileage out of the old “evolution is just a theory” canard, and I don’t think it’s coincidental that the claim is only a small mental hop away from “it’s just an opinion.” The layperson is left with the intuitive sense that belief in evolution is either unjustified or untrue, and this intuition is strengthened by overemphasis of the “controversy” over evolutionary theory. The (distinctly American) reticence to accept evolutionary theory need not have anything to do with religion, as is often assumed; rather, it’s that theoretical knowledge falls outside the realm of what Plato would have called knowledge, and so qualifies as what the layperson considers opinion. Of course, there’s a mistake in this way of thinking. Plato’s dilemma is a false one. I’ve actually gone so far as to ban use of the word “opinion” in my classes in order to guard against this error (which always makes for some admittedly sadistic fun when I have students read from a translation of “Meno”). There is a third way, and we need to recognize that some beliefs can’t be known, but are more justifiable than mere opinion. The third way, between knowledge and opinion, is science. I won’t dwell too much on what science is or how science gets practiced. All we need to bear in mind is that scientific beliefs are justifiably held, but only provisionally believed to be true (if at all), and so mark a halfway point between knowledge and opinion.