Monday, February 12, 2018

Physicist Lawrence Krauss on a podcast

The Sam Harris podcast #115 interviews a physicist:
In this episode of the Waking Up podcast, Sam Harris speaks with Lawrence Krauss and Matt Dillahunty about the threat of nuclear war, science and a universal conception of morality, the role of intuition in science, the primacy of consciousness, the nature of time, free will, the self, meditation, and other topics. This conversation was recorded at New York City Center on January 13, 2018.
You can also get it on YouTube.

It is amusing to hear these guys ramble on about their beliefs about consciousness, free will, etc., while all the time claiming to be such super-rational scientists that the word "believe" does not even apply to them.

I heard a story (from Ben Shapiro) that Sam Harris was in another public discussion on free will, and a questioner from the audience said, "You convince me that we have no free will, but I have a 5-year-old son. What should I tell him?" Harris was flustered, and then said to lie to the kid.

There are probably some things that he thinks that his audience is too stupid to understand. What else is he lying about?

Harris referred to how he spent years meditating and taking hallucinogenic drugs, after dropping out of college. Krauss was noticeably skeptical that he learned so much from taking drugs, but Harris made an analogy to Krauss studying mathematics. That is, just as Harris's LSD hallucinations might seem like nonsense to others, Krauss looking at a page of mathematical symbols also looks like nonsense to most people.

No, it is a stupid analogy. Advanced mathematics is demonstrably useful for all sorts of purposes. Nobody ever accomplished anything while on LSD. This sort of reasoning gives legitimacy to the nuttiest ideas, and it is surprising to get it from someone who made most of his reputation by badmouthing religion.

One quibble I have with Krauss is that about about 1:00:00, he says:
[questioning that] classical reason and logic should guide our notions.

The point is that classical reason and logic, when it comes to the world, are often wrong because our notions of classical reason and logic are based on our experience
Someone else says he is wrong, because the logic of Venn diagrams is not based on experience. Krauss sticks to his point, and says Venn diagrams can be wrong because an electron can be in two places at once.

I think that the problem here is that physicists, like Krauss, have a flawed view of mathematics. To the mathematician like myself, classical reason and logic are never wrong.

Electrons are not really in two places at once. But even if they were, they would not achieve some sort of logical impossibility. Nothing ever achieves a logical impossibility. It might be that you have a theory that is ambiguous about the electron location, or that there are 2 electrons, or something else. In my view, the electron is a wave that is not localized to a point, and separate places could have a possibility of observing it. Your exact view depends on your interpretation, but you are still going to use classical mathematics in any case.

I am still trying to get over Aaronson believing in many-worlds. It is hard for me to see how these smart professors can believe in such silly things.

Philosopher of Physics Tim Maudlin defends his favorite interpretations on Aaronson's site, and also has a new paper on The Labyrinth of Quantum Logic.

Quantum logic is a clever way to try to explain puzzles like the double slit, where light goes thru the double slit like a wave, but attempts to understand the experiment in terms of individual photon going thru one slit or the other are confusing. Quantum logic declares that it can be true that "the photon goes thru slit 1 and the photon goes thru slit 2", but the rules of logic need to be changed so that it does not imply that either "the photon goes thru slit 1" or "the photon goes thru slit 2" is true. In math jargon, they deny the law of the excluded middle.

As Maudlin explains, there has been some historical interest in quantum logic, but it has never proved useful, or even made much sense. No physical experiment can possibly effect our laws of mathematics. You can tell yourself that quantum logic explains the double slit experiment, but that's all you can do. It doesn't lead to anything else.

Quantum probability is another topic where people try to over-interpret quantum mechanics to try to tell us something about mathematics. Some say that quantum mechanics discovered that probabilities can be negative, or some such nonsense. Again, you can choose to think about things that way, but it has no bearing on mathematical probability theory, and probabilities are never negative.

The Harris and Krauss show was repeated in Chicago, with this summary:
I asked Sam at dinner if he was going to talk about free will, but he said that they’d covered that topic in a previous event, which was archived on his podcast. Nevertheless, one guy asked the speakers how, given the absence of free will, they could advise him how to cure his addiction to alcohol. That was a good question, because Sam and Lawrence are hard determinists (Matt is a compatibilist but still a determinist.) Answering that question without getting balled up in an infinite regress is quite difficult. If, for instance, you tell someone that they can choose to put themselves in a milieu where there is no alcohol and also surround themselves with supportive people (yes, that’s how it could be done), you risk making people think that you can make such a choice freely, instantiating dualism. I suppose a good answer is that one’s brain is a computer that weighs various inputs before giving the output (a decision), and that the advice Sam gave — which could of course influence the actions of the addict — was also adaptive, in the sense that he was giving strategies that his brain calculated had a higher probability of being useful. Further, we all try to be helpful to cement relationships and get a good reputation—that’s part of the evolved and learned program of our brains. But of course Sam had no “free” choice about his advice, and this shows the difficulty of discussing free will with those who haven’t thought about it. ...

The final remark came from Lawrence, who said that every time he stays in a hotel, his own gesture to diminish faith was to take the Gideon Bible, wrap it in a piece of paper, and throw it in the trash. Sam remarked dryly, “And that’s why atheists have such a good public image.”
Alchololics Anonymous teaches that alcoholics have little or no free will, and that they are doomed to remain alcoholics no matter what they do. They are advised to accept what they do not have the free will to change.

It is weird to worry about instantiating dualism.

Krauss is one of the better and more level-headed physicists in the public eye, but he thinks that he is helping people by telling them that they have no free will, and trashing their Bibles. He is good when he sticks to the physics.

1 comment:

  1. Negative probability could be a useful concept. Remember that negative numbers were not accepted until very late in the game. You can say that a propensity opposite another is negative. The problem with their view of QM is that they are probabilistic essentialists.

    Your point about logic is spot on. The double bind in Eastern philosophy is not really transcended but accepted as a "true contradiction." It's pure nonsense that doesn't understand you have to refine the language or assumptions in order to describe something logically. 1 + 1 is not equal to 2 when considering raindrops. Context is key. Logic is about the inviolable rules of thought.