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Logic

Do false statements imply contradictions? Consider the truth table for logical implication. P...........Q.............P-> Q T...........T.............. T T...........F...............F F...........T...............T F...........F...............T Notice that for a false statement P, the last two rows of the truth table, both Q and ~Q follow. No matter what Q is, it's truth follows from false statement P, as the third row shows. We can therefore take Q to be "P is true." From here it follows that a false statement P implies it's own truth, as the third row shows. Do false statements really imply their own truth? Do they really imply contradictions? Are false statements also true?

Imagine that someone finds it useful to define a new term -- "mimp," say. The newly-defined term is a conjunction, i.e., it's used to link sentences together, and it works this way: "P mimp Q" is false when "P" is true and "Q" is false. Otherwise it's true. With this definition in hand, consider the sentence "New York city has fewer than 150,000 resident mimp the next US president will come from New York." Give our definition, this is true. Our definition of "mimp" guarantees that whenever "P" is false, "P mimp Q" is true. Looking at "→" this way may help with your puzzle. The symbol "→" (alternatively "⊃" ) is one that logicians found useful to define, and its definition is given by the rule above. Whether it matches any connective in natural language is open to doubt, and in particular, it does not mean what we mean by the phrase "logically implies." After all, "New York City has fewer than 150,000 residents" does not logically imply that the next US President will be from New York. It...
Perception
Space

Would the idea of 3 dimensional space be possible without vision?

The answer seems pretty clearly to be yes. Touch and hearing both convey information about dimension. Think, for example, about the fact that a sound can be above you, or in front, or two the side. Or think of how you could tell that object A is taller than object B, but object B is wider than object A just by using your sense of touch. If you're interested, here's a link to a video about a remarkable Turkish painter, blind from birth but able to convey subtle information about perspective.
Mind

Why are people so skeptical about the notion that a sufficiently advanced computer program could replicate human intelligence (meaning free will insofar as humans have it; motivation and creativity; comparable problem-solving and communicative capacities; etc.)? If humans are intelligent in the way we are because of the way our brains are built, than a computer could be constructed that replicates the structure of our brains (incorporating fuzzy logic, neural networks, chemical analogs, etc). Worst comes to absolute worst, a sufficiently powerful molecular simulator could run a full simulation of a human brain or human body, down to each individual atom. So there doesn't seem to be anything inherent in the physicality of humans that makes it impossible to build machines with our intelligence, since we can replicate physical structures in machines easily enough. If, however, humans are intelligent for reasons that do not have anything to do with the physical structure of our brains or bodies - if there...

My colleague and I disagree somewhat here, though perhaps on everything essential to your question, we agree. We all agree that in principle the right kind of "machine" could be every bit as conscious, free, etc.as you and I. And Prof. Nahmias may well be right when he says that if a robot of the C3PO sort acted enough like us, we'd have a very hard time not thinking of it as conscious. I even agree with my co-panelist that people's religious beliefs and the relatively crude character of our actual gadgets may be part of the reason why many people don't think a machine could be conscious. So where's the residual disagreement? It's on a point that may not be essential, given the way you pose your question. Prof. Nahmias thinks that replicating the functional character of the mind would give us reason enough to think the resulting thing was conscious. I'm not inclined to agree. But that has nothing to do with belief in souls (I don't believe in them and don't even think I have any serious idea...
Religion

I recently was in an " Ask an Atheist" panel at a predominantly Lutheran college, and after asserting that the burden of proof lies on the theist, someone claimed that a deeply spiritual person has knowledge that is only available to them. In other words, regarding what is morally correct or anything else god could want us to do, a theist is justified doing things akin to Abraham attempting to sacrifice Isaac because they have a certain kind of knowledge that justifies doing so despite all evidence that suggests it is wrong. Is this logically or epistemologically sensical, especially regarding morality? What about people like Hildegard of Bingen who claimed to receive visions from God and know this is the case beyond all doubt?

Burden of proof arguments can be tricky. Atheists often say that believers have the burden of proof, but at the least that depends on what's being asked. Is the claim that the believer is irrational or intellectually blameworthy if s/he doesn't meet this burden? As we'll see below, that's a lot less obvious than one might think. That said, I agree with my co-panelist that there's something off here. Saying just what may be a bit tricky, however. One view of knowledge is that it's justified true belief, where the justification is something that could be articulated. However, that view has come in for a good deal of criticism. The most relevant problem is that there seem to be cases of real knowledge where the knower couldn't articulate any justification. Animals plausibly know things. So do young children. For that matter, there seems to be a good deal of general knowledge that most of us possess, that really is knowledge, but that that most of us would be unable to justify. Reliabilists ...
Ethics
Mind

'Normal' people don't do very bad things (murder, rape, etc), so if someone does something bad, can't we assume that the person is sick rather than evil? Why is it that people with mental disabilities, people with addictions, etc. can use that as their excuse and usually get people to pity them while other "crazy" people don't get any pity whatsoever and instead get thrown into prison for the rest of their lives?

We need to be careful to avoid equivocating here. What we can safely say is that most people don't do very bad things; the people who do are in the tail of the statistical distribution. However, that isn't enough to count them as mentally ill or disabled. To come to that conclusion, we'd need to know whether the person was able to reason effectively, whether they have adequate impulse control, whether they're subject to delusion, and various other such things. The mentally ill, the addicted and people with various other mental disabilities are - as the word suggests - disabled. In one way or another, they aren't able to function as we are. If a person with severe dyslexia misread a set of instructions and the result was some misfortune, it would make sense to take that into account when deciding how much to blame them. What's easy for most of us (reading instructions) might be much harder for them, through no fault of their own. But if a person's frontal lobes don't work properly and they don't...
Existence

I have been a bit curious about the notion of the use of “possible worlds” as a way of communicating whether a proposition is either empirically or rationally true. When a proposition is said to be necessarily true (e.g. Circles are round) it is said that there is no possible world in which circles exist and are not round; circularity and roundness are inherently tied together by their nature. However, it seems upon further reflection that the use of the quantifier “all possible worlds” could only suggest all possible worlds in which ideas or abstract objects like circles and the concept of roundness are like our actual world; or, in a related sense, where there exist beings whose deductive logical “systems” are like ours. If this is true is it possible that our invoking the use of the phrase “all possible worlds” should really indicate “all possible worlds like our own”? While it may be nonsensical to state that there are square circles in some possible world, does it follow that this cannot be true in...

It seem that some issues are getting blurred here. You suggest that when we say there are no possible worlds with round squares, we're implicitly talking only about worlds where the concepts of 'round' and 'square' are as they are in our world, or -- perhaps you see this as the same thing -- only in worlds with beings who think the way we do. But that makes it sound as though it's a matter of how people talk or think. The real point is this: we use the words 'round' and 'square' to pick out certain concepts. People who don't speak English might use different words. Some creatures may not have these concepts at all. And there could be square things or round things -- things that fit the concept we're getting at -- even if there were no thinkers at all. But to revert to world-talk, there aren't any worlds where any round things are also square things --even though there might be worlds where beings use the words 'round' and 'square' to pick out concepts different from ours that don't exclude one another. ...
Logic

There is a simple reasoning. Which is better, bread or love? It seems love is better than nothing. For sure bread is better than nothing. So bread is better than love. Of course this is a wrong reasoning. But I wonder whatever logical mistake is made here?

There are two problems here. First, let's look at an argument about sports teams that's similar to yours but different in a simple way: The Lions are better than the Tigers The Bears are better than the Tigers. Therefore, the Bears are better than the Lions This is flat-out fallacious. The premises give us no more reason to think the Bears are better than the Lions than that the Lions are better than the Bears. But the structure -- X is better than Z; Y is better than Z; therefore Y is better than X -- is the one I think you were thinking of. I'm guessing that what you really had in mind was some variation on this old chestnut: Bread is better than nothing. Nothing is better than God. Therefore, bread is better than God This at least looks as though it could be valid; the form seems to be: X is better than Y; Y is better than Z; therefore X is better than Z. If we take as given that "better than" is transitive, as logicians would say, then the form will lead us to a true conclusion...
Ethics
Sex

I told my friend that I didn't pursue a second date with a woman I met through an Internet dating site because she wasn't physically attractive enough. My friend said it was wrong to "judge" a person by their looks. I said that I wouldn't date my friend Travis either based on his looks and you wouldn't disagree with that. My friend said that the reason that I wouldnt date Travis was that Travis is a man and I'm a heterosexual. Yes but what is a man I asked other than someone who "looks" different than a woman? So isn't heterosexuality about discriminating against a person based on their looks? And if that's the case and if we as a society are okay with diacriminating against a person just because they don't look like a certain gender then why is it often considered wrong to not date someone based on looks that go beyond gender? It might sound like I am resorting to a kind of logical trickery but I think I have a good point. People often speak of a romantic relationship as if it were an elevated...

Physical attraction is part of what makes a romantic relationship, and so if romance was what you wanted, not being attracted would matter. This also explains why it would be strange to say that a heterosexual is discriminating in an objectionable way against people of the same sex just because s/he doesn't have romantic relationships with them. (We can turn this around, of course. A gay man isn't discriminating against women in some untoward way just be cause he doesn't want to have romantic relationships with them.) That much is obvious. But there's still some subtlety in the background. You said you didn't pursue this possibility because the woman "wasn't attractive enough." That could mean a couple of things. One is that you didn't find her sexually attractive: for whatever reason, there was none of that sort of spark. More on that below, but so far, no foul. However, you might have meant that she didn't meet some conventional standard of attractiveness, quite apart from your own reaction....
Ethics

Upon learning that Osama bin Laden has died, many people decided to take to the streets and celebrate. This is the celebration of a person's killing, something which is extremely rarely celebrated. On the one hand, his death represents the putative end to a threat (though the jury is out on whether that's true); on the other hand, he was a living human being and, though a criminal, deserved a legal process rather than a killing. Should we be rejoicing that bin Laden was killed, or should we let it pass as an evil lesser than it would have been to let him run free?

Lots of good questions here. I see two main issues in what you write. The first, which you close with, is whether the killing was appropriate in the first place. The second, implicit in where you begin, is what to make of the celebration of bin Laden's death. Start with the first. The administration claimed, at least as of a few days ago, that the intent was to take bin Laden alive, but that he was killed because he resisted in some not-clearly specified way. However, let's assume for the sake of exploring what to say that the intent was never to take him alive in the first place. You say that even he deserved a legal process rather than a killing, and there's no doubt: the idea that the government should be executing people without judicial process is a very disturbing one. Ideally, one might think, bin Laden should have been brought before some judicial body, whether an American court or the International Criminal Court, though there's room to doubt the prudence of that project. In any...
Physics

Henry Stapp (a physicist at Berkeley) in his book The Mindful Universe states: "Let there be no doubt about this point. The original form of quantum theory is subjective, in the sense that it is forthrightly about relationships among conscious human experiences, and it expressly recommends to scientists that they resist the temptation to try to understand the reality responsible for the correlations between our experiences that the theory correctly describes. The following brief collection of quotations by the founders gives a conspectus of the Copenhagen philosophy: Heisenberg (1958a, p. 100): The conception of objective reality of the elementary particles has thus evaporated not into the cloud of some obscure new reality concept but into the transparent clarity of a mathematics that represents no longer the behavior of particles but rather our knowledge of this behavior" As philosophers, what is your take on these statements? It appears to me that these quite distinguished physicists are saying...

It's certainly true that Bohr and Heisenberg, among others, interpreted quantum theory in a way that put the knowing subject center stage, but this is just one part of a controversy that continues to this day. Einstein and Schrödinger, for rather different reasons, resisted these more epistemic interpretations, and while some would say that Einstein lost in the wake of the investigations of Bell's inequality, Bell himself was very attracted to realist interpretations of quantum theory. "Collapse" interpretations, such as the so-called GRW theory, are not epistemological interpretations, nor is Bohmian mechanics (a development of de Broglie's pilot wave idea), nor, for that matter, is the Everett interpretation (roughly, the "many-worlds" interpretation.) So the simplest thing to say is that there partisans on both sides and the controversy is ongoing. If you'd like to read more, you could do worse than to get a copy of Alistair Rae's Quantum Physics: Illusion or Reality? or John Polkinghorne's ...

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