Michael Huemer

The brain-in-a-vat argument for skepticism is best formulated, not using the closure principle, but using the “Preference Principle,” which states that in order to be justified in believing H on the basis of E, one must have grounds for preferring H over each alternative explanation of E. When the argument is formulated this way, Dretske’s and Klein’s responses to it fail. However, the strengthened argument can be refuted using a direct realist account of perception. For the direct realist, refuting the SIV scenario is not a precondition on knowledge of the external world, and only the direct realist can give a non-circular account of how we know we’re not brains in vats

In The Structure of Empirical Knowledge , Laurence BonJour argues that coherence among a set of empirical beliefs can provide justification for those beliefs, in the sense of rendering them likely to be true. He also repudiates all forms of foundationalism for empirical beliefs, including what he calls "weak foundationalism" (the weakest form of foundationalism he can find). In the following, I will argue that coherence cannot provide any justification for our beliefs in the manner BonJour suggests unless some form of foundational justification is assumed. In other words, the argument that BonJour gives in favor of the thesis that coherence provides a kind of justification succeeds if and only if some beliefs have (at least weak) foundational justification.

Richard Fumerton’s “Principle of Inferential Justification” holds that, in order to be justified in believing P on the basis of E, one must be justified in believing that E makes P probable. I argue that the plausibility of this principle rests upon two kinds of mistakes: first, a level confusion; and second, a fallacy of misconditionalisation. Furthermore, Fumerton’s principle leads to skepticism about inferential justification, for which reason it should be rejected. Instead, the examples Fumerton uses to motivate his principle can be accounted for using a different principle: in order for S to be justified in believing P on the basis of E, it must be true that E makes P probable. The latter principle can be independently motivated and does not lead to skepticism

I defend the principle of Phenomenal Conservatism, on which appearances of all kinds generate at least some justification for belief. I argue that there is no reason for privileging introspection or intuition over perceptual experience as a source of justified belief; that those who deny Phenomenal Conservatism are in a self-defeating position, in that their view cannot be both true and justified; and that thedemand for a metajustification for Phenomenal Conservatism either is an easily met demand, or is an unfair or question-begging one.

People want things, and they tend to act in such a way as to get the things they want, to the best of their ability.1 Sometimes our wants conflict with each other, so that we are forced to choose between different things that we want. When this happens, we normally choose the thing that we want more, over the thing that we want less. Behaving in this way is what we call “rational”; more specifically, it is “instrumentally rational.” Instrumental rationality consists in choosing the means that best achieves one’s goals, according to the information one has.

Michael Huemer argues that there is a tension between two principles putatively essential to Rand's ethics: the principle of egoism, which states that the only reason for doing (or not doing) anything is that it will serve (or frustrate) one's own interests; and the principle that one must not sacrifice others. Huemer considers several arguments that Rand offers for the second principle but finds that each involves either implausible empirical assumptions or assumptions that conflict with egoism. Huemer suggests that Rand may not be an egoist in the usual sense; her positions are much more consistent with the second principle.

Illegal drugs are not inherently unclean, any more than alcohol, tobacco, or canola oil. All of these are simply chemicals that people choose to ingest for enjoyment, and that can harm our health if used to excess. Most of the sordid associations we have with illegal drugs are actually the product of the drug laws: it is because of the laws that drugs are sold on the black market, that Latin American crime bosses are made rich, that government officials are corrupted, and that drug users rob others to buy drugs.

The brain-in-a-vat argument for skepticism is best formulated, not using the closure principle, but using the “Preference Principle,” which states that in order to be justified in believing H on the basis of E, one must have grounds for preferring H over each alternative explanation of E. When the argument is formulated this way, Dretske’s and Klein’s responses to it fail. However, the strengthened argument can be refuted using a direct realist account of perception. For the direct realist, refuting the SIV scenario is not a precondition on knowledge of the external world, and only the direct realist can give a non-circular account of how we know we’re not brains in vats.

Should the recreational use of drugs such as marijuana, cocaine, heroin, and LSD, be prohibited by law? Prohibitionists answer yes. They usually argue that drug use is extremely harmful both to drug users and to society in general, and possibly even immoral, and they believe that these facts provide sufficient reasons for prohibition. Legalizers answer no. They usually give one or more of three arguments: First, some argue that drug use is not as harmful as prohibitionists believe, and even that it is sometimes beneficial. Second, some argue that drug prohibition “does not work”, i.e., is not very successful in preventing drug use and/or has a number of very bad consequences. Lastly, some argue that drug prohibition is unjust or violates rights. I won’t attempt to discuss all these arguments here. Instead, I will focus on what seem to me the three most prominent arguments in the drug legalization debate: first, the argument that drugs should be outlawed because of the harm they cause to drug users; second, the argument that they should be outlawed because they harm people other than the user; and third, the argument that drugs should be legalized because drug prohibition violates rights. I shall focus on the moral/philosophical issues that these [134] arguments raise, rather than medical or sociological issues. I shall show that the two arguments for prohibition fail, while the third argument, for legalization, succeeds.

Recent results in probability theory have cast doubt on coherentism, purportedly showing (a) that coherence among a set of beliefs cannot raise their probability unless individual beliefs have some independent credibility, and (b) that no possible measure of coherence makes coherence generally probability-enhancing. I argue that coherentists can reject assumptions on which these theorems depend, and I derive a general condition under which the concurrence of two information sources lacking individual credibility can raise the probability of what they report.

Debunking skeptics claim that our moral beliefs are formed by processes unsuited to identifying objective facts, such as emotions inculcated by our genes and culture; therefore, they say, even if there are objective moral facts, we probably don’t know them. I argue that the debunking skeptics cannot explain the pervasive trend toward liberalization of values over human history, and that the best explanation is the realist’s: humanity is becoming increasingly liberal because liberalism is the objectively correct moral stance.