If someone figured out how to build a perpetual motion machine, this would mean that something formerly but falsely believed to be law of nature would have been found not to be. It wouldn't mean that a bona fide law of nature had been violated. Or at least that's a reasonable thing to say. But I've assumed that God has nothing to do with the Ever-Whirling Whirligig. If there's a God, that complicates things. There's a view that says there can't be miracles because by definition, miracles are violations of laws of nature and by definition, a false generalization isn't actually a law of nature, but that's a poor argument. If there is a supernatural God, then the reasonable way to understand laws of nature is that they're generalizations that hold true without special divine intervention. A good analogy (can't remember who offered it) is that the laws of nature are like the working of a clock when nothing messes with its mechanism. If God messes with the natural mechanisms and suspends them in...

You ask if it's morally bad to profit from a crime. Since the answer seems pretty clearly to be yes, I'm a bit unsure what would count for you as saying why, but let's try an example: Robin's spouse carries a large life insurance policy. Robin kills him—a morally bad thing, I hope you'll agree—and then gets the payout from the policy, thereby profiting from the crime. Sounds bad to me. Consider two cases. (1) someone commits a crime—a theft, let's say— but they do it in order to help some desperate but otherwise innocent person. (2) Someone commits the same crime, but they do it simply because they want the money, which in fact they manage to get away with keeping and using. Most of us would say that the first case is less egregious, the wrongdoer of less bad character, and the act more forgivable. Is there a deeper explanation? More than one, no doubt. If my profit flows from a crime, then I don't deserve the benefit I got, and we care about whether people deserve what they're getting. Also, if we...

The answer is surely that it's not unethical or wrong or immoral to favor one team over another. But there's an interesting issue in the background. At least some views of what morality calls for say that we should be impartial. If I'm a utilitarian, then everyone's pleasure and pain count equally. If I'm a Kantian, then I should act only on maxims that I could will to be universal laws. But in that case, it seems, I can't favor particular people—or particular sports teams. Whether this is really what utilitarianism or Kantianism call for, this would be crazy. It's also an issue that comes up in an important essay by the British philosopher Bernard Williams ("Persons, Character and Morality," 1976.) Toward the end of the essay, he considers a hypothetical raised by another philosopher, Charles Fried. Fried imagines a man who is in a position to save one of two people, one of whom is his wife. Fried is clear that it should be acceptable for the man to save his wife instead of the stranger. But Williams...

Suppose that instead of a computer producing a simulation, we have an army of thousands of worker-bee science grad students performing and assembling vast numbers of calculations matching all the steps that a computer simulation would call for. Suppose the results are consistent with observation. We wouldn't ask whether what's being simulated is really nothing but desperate grad students chained to desks doing tedious math. Computer simulations are ways of finding out what our equations and assumptions entail. In an example where it would be feasible to calculate the behavior of the model by hand, we wouldn't doubt that the real target of the exercise is external-world stuff—particles or economic agents or pathogens or whatever. That doesn't change if we move to cases where there's no serious possibility of doing the calculations by hand. The computer simulation doesn't represent itself . It represents what it simulates. If we've done things right, the representation will be more or less accurate....

You pose the question twice: first by asking if people owe a debt and second by asking if behaving in certain ways would be ungrateful . I think the difference matters. I don't know whether a child owes a debt to her parents—at least not in a certain strict sense. The primary use of the language of debt deals with contracts, promises and, in any case, cases of mutual consent. There are other uses, but the further they are from the primary ones, the harder it is to be sure of their force. Fortunately, it doesn't matter. Suppose we agree that the child doesn't literally owe her parents a debt for raising her—even if they did it lovingly, conscientiously and well. But would it be ungrateful for her to turn her back on her parents because, say, her new social circle made it embarrassing for her to have these people as parents? I think the answer is obvious enough. Asking what the daughter owes to her parents invites quibbles and evasion. But moral language is broader and more supple than...

It seems not. In any case, the discussion of this saying in Wikipedia is actually pretty good: https://en.wikipedia.org/wiki/I_know_that_I_know_nothing

This argument is a variation on solutions that assume a non-omnipotent God. If God doesn't have the power to prevent all evil, then the fact that there is evil would be no surprise. This version's variation is just that God gets tired and sometimes has to rest. For the moment, leave aside the point that this is far too anthropomorphic a conception of God for most theologians' tastes. And leave aside that at least some theologians would say that anything less than an omnipotent god doesn't deserve the label "God" to begin with. (I'm sympathetic to the first point, less so to the second.) Ask instead what patterns of evil we might expect if we accept this explanation. Suppose there's a flood and people are drowned. Is the idea that if God hadn't been napping, they would have been saved? Suppose some crazy person walks into a school with a gun and kills a bunch of people. Are we suppose to say that they would have been saved if God hadn't been tired? It's probably safe to say that at every single minute...

There are interpretations of quantum mechanics that make related claims. There's the transactional interpretation, proposed by John Cramer and developed more recently by Ruth Kastner. It holds that quantum events such as measurement results occur when there is a "handshake" between an advanced wave, traveling from future to past, and a retarded wave, traveling from past to future. The so-called two-state vector formalism, pursued in recent years by Yakir Aharanov and Lev Vaidman, is in some ways similar. Huw Price has long argued that if we allow for backward causation, we can avoid having to posit faster-than-light action at a distance. Some people have argued that in certain cases, quantum teleportation involves information moving from future to past. But all of this is controversial and it would be hard to argue that a consistent understanding of quantum mechanics requires backward causation. To which we should add: these interpretations do not claim that quantum mechanics can exploit any...

I'm sure that Stephen Maitzen will have useful things to say, but I wanted to chime on in this one. You have just given a perfectly consistent description of what actually happens in a simple polarization experiment that I use most every semester as a teaching tool. Classical logic handles this case without breaking a sweat. But there's another point. You've described the phenomenon in terms of light waves. That's fine for many purposes, but note that the wave version of the story of this experiment comes from classical physics, where (for the most part at least) there's no hint of logical paradox. The classical explanation for the result is that a polarizing filter doesn't just respond to a property that the light possesses. It also changes the characteristics of the wave. Up-down polarized light won't pass a left-right filter, but if we put a diagonal filter between the two, the classical story is that the intermediate filter lets the diagonal component of the wave pass, and when it does, the light...

It's important sometimes to distinguish between intellectual problems and other kinds of problems. Many, maybe most of the people I know well are atheists. They agree with you: the world doesn't contain any meaning of its own, it doesn't care about us, and nothing is permanent. The difference between most of those people and you isn't that they've had some philosophical insight that you haven't. The difference, I would gently suggest, is that you are depressed and they aren't. I'm not a psychologist, but the way you describe your state of mind sounds like a textbook depression. How we think about things is certainly relevant when we're depressed, but the way it's relevant isn't just about content. Two people can both think that the world is indifferent to us, but for one this isn't an intrusive idea. It doesn't stop her from enjoying her work and her friends and her pastimes. It doesn't keep her awake at night. The other finds himself perseverating about it, brain caught in a loop. Getting out of that...