Peter Baumann

The well known Monty Hall-problem has a clear solution if one deals with a long enough series of individual games. However, the situation is different if one switches to probabilities in a single case. This paper presents an argument for Monty Hall situations with two players (not just one, as is usual). It leads to a quite general conclusion: One cannot apply probabilistic considerations (for or against any of the strategies) to isolated single cases. If one does that, one cannot but violate a very plausible non-arbitrariness condition and is led into a Moore-paradoxical incoherence. Even though arguments for switching are correct as applied to series of games, they don’t say anything useful about what rationality demands in a single case.

1. Here is a very simple game. You come up with a number and I come up with a number. If I come up with the higher number, I win; otherwise you win. You go first. Call this ‘The Very Simple Game’. Few would play it if they had to go first and many if they are guaranteed to go second.2. Here is another one. You come up with a number n and I come up with a number m. If m times 1/ n > 1, then I win; if not, then you win. You go first. Call this ‘Still The Very Simple Game’. Since I win just in case m is greater than n, this game collapses into The Very Simple Game. Few people will play it if they have to go first.3. Here is a third one. Let us call it ‘Looks Like A Tricky Game’. Suppose you have a choice between exactly two actions: keep holding on to some thing t ; hand t over to me and accept my offer to give you, with some probability p, some thing with utility m.Suppose, you are a maximizer of expected utility with …

Philip Kitcher recently argued for a reconstruction in philosophy. According to him, the contemporary mainstream of philosophy has deteriorated into something that is of relevance only to a few specialists who communicate with each other in a language nobody else understands. Kitcher proposes to reconstruct philosophy along two axes: a knowledge axis and a value axis. The present article discusses Kitcher's diagnosis as well as his proposal of a therapy. It argues that there are problems with both, and it ends with an alternative view of what some core problems of the profession currently are.

This paper argues against common views that at least in many cases Robert Nozick is not forced to deny common closure principles. More importantly, Nozick does not – despite first (and second) appearances and despite his own words – deny closure. On the contrary, he is defending a more sophisticated and complex principle of closure. This principle does remarkably well though it is not without problems. It is surprising how rarely Nozick’s principle of closure has been discussed. He should be seen not so much as a denier of closure than as someone who’s proposing an alternative, more complex principle of closure.

Amongst those who answered Molyneux’s question in the negative or at least not in the positive, George Berkeley is of particular interest because he argued for a very radical position. Most of his contribution to the discussion can be found in his Essay towards a New Theory of Vision. I will give an exposition of his view (2) and then move on to a critical discussion of this kind of view, - what one could call the “Berkeleian view” (3). I think that the problems of what has become a standard negative answer to the question (mainly brought forward by empiricists) become very clear in Berkeley’s case and one can also learn a lot from this.

This paper argues that three plausible principles are mutually inconsistent: One ought to assert only what one knows; If it is proper to assert some proposition q, then it is, barring special and not very common circumstances, proper to assert any proposition p from which q has been competently inferred; and Some propositions are both properly assertible and known by competent inference from propositions which one does not know. Each pair of two principles constitutes an argument against the remaining principle, but which principle should one drop?

Kant's political philosophy in general is characterized by two aspects which sometimes compete with each other and sometimes supplement each other: an individualist element on the one hand and a social or "communitarian" element on the other hand. This paper deals with Kant's theory of private property. It attempts to show something that is usually overlooked in the secondary literature: that Kant has two, not just one argument for property. One is based on his theory of freedom and expresses the individualist aspect of his thinking. The other argument is based on Kant's principle of right and expresses the social aspect of his political thought. Despite some problems with his arguments the complexity of Kant's theory remains impressive.

In this paper I respond to P.D. Magnus’ critique of an earlier paper of mine on Thomas Reid’s theory of common sense. In the earlier paper (The Scottish Pragmatist? The Dilemma of Common Sense and the Pragmatist Way Out, Reid Studies 2, 1999, 47-57) I argued that Reid faces a dilemma between dogmatism and scepticism but that there are also hints in his work towards a pragmatist way out of the problem. P.D. Magnus, in a response to this paper (Reid’s Dilemma and the Uses of Pragmatism, Journal of Scottish Philosophy 2, 2004, 69-72), criticizes me for misidentifying the kind of pragmatism one can find in Reid. In this paper I defend my interpretation of Reid and spell the relevant kind of pragmatism out in more detail.

Are our beliefs mostly true? Donald Davidson has proposed some very interesting arguments in favor of his "extended claim" that most our beliefs must be true. The main aim of this paper is to show that Davidson's arguments are not convincing. The most well known of his arguments is the argument of the "omniscient interpreter". The conceivability of a totally ignorant interpreter, however, shows that this argument fails. Davidson offers two more arguments for his extended claim: one of them based on his holism of the propositional attitudes, the other one based on his externalism of language and thought. Both arguments, however, do not sufficiently support the extended claim. Hence, it must remain open at least whether we live in one of the best possible epistemic worlds.

Hájek has recently presented the following paradox. You are certain that a cable guy will visit you tomorrow between 8 a.m. and 4 p.m. but you have no further information about when. And you agree to a bet on whether he will come in the morning interval (8, 12] or in the afternoon interval (12, 4). At first, you have no reason to prefer one possibility rather than the other. But you soon realise that there will definitely be a future time at which you will (rationally) assign higher probability to an afternoon arrival than a morning one, due to time elapsing. You are also sure there may not be a future time at which you will (rationally) assign a higher probability to a morning arrival than an afternoon one. It would therefore appear that you ought to bet on an afternoon arrival. The paradox is based on the apparent incompatibility of the principle of expected utility and principles of diachronic rationality which are prima facie plausible. Hájek concludes that the latter are false, but doesn't provide a clear diagnosis as to why. We endeavour to further our understanding of the paradox by providing such a diagnosis.

We often describe lives (or parts of lives) as meaningful or as not meaningful. It is also common to characterize them as more or less meaningful. Some lives, we tend to think, are more meaningful than others. But how then can one compare lives with respect to how much meaning they contain? Can one? This paper argues that (i) only a notion of rough equality can be used when comparing different lives with respect to their meaning, and that (ii) the relation of being more meaningful is not transitive. It follows that all attempts to rank different lives in terms of meaning can at best lead to partially indeterminate and incomplete rankings. One should also give up on the idea of “maximizing” meaning. I will use Thaddeus Metz’s important recent book “Meaning in Life. An Analytic Study” as a foil for my discussion.

For each of the many goals of an agent it is true that the agent wants its realization. Given further very plausible assumptions, one can show that there is no good reason for an agent not to want the realization of all of his goals. However, it seems also true that reaching all of one’s goals would be extremely boring; most human beings would consider such a life not worth living. In this respect, leading a life is like playing some game: A game loses its point if one always easily wins. Human agents not only pursue goals but they also have the second-order desire to lead the life of a goal-pursuer. More precisely, they want to be goal-pursuers such that many but not all of their goals are being realized. I argue here that they have a good reason not to want the realization of all of their goals. Now, all this constitutes an antinomy: Apparently, there are very plausible arguments both for affirming as well as denying that an agent has good reasons not to want the realization of his goals. This antinomy is similar to the preface-paradox about beliefs which has a convincing solution (due to Frank Ramsey). I argue, however, that there is no such solution in the case of goals. This leaves us with the question what a solution could look like.

Epistemic contrastivism is the view that knowledge is a ternary relation between a person, a proposition and a set of contrast propositions. This view is in tension with widely shared accounts of practical reasoning: be it the claim that knowledge of the premises is necessary for acceptable practical reasoning based on them or sufficient for the acceptability of the use of the premises in practical reasoning, or be it the claim that there is a looser connection between knowledge and practical reasoning. Given plausible assumptions, epistemic contrastivism implies that we should cut all links between knowledge and practical reasoning. However, the denial of any such link requires additional and independent arguments; if such arguments are lacking, then all the worse for epistemic contrastivism.

According to reliabilist conceptions of knowledge, knowledge implies reliable true belief. Since reliability is an irreducibly probabilistic notion, one's view of knowledge also depends on one's view of probability. If one believes that all probability is subjective probability, knowledge becomes a relativized concept: knowledge is relative to a given body of beliefs of a given person at a given time. Since such a relativized conception of knowledge is extremely implausible and since reliabilism seems to capture at least part of the truth, one should rather give up a purely subjective view of probability.