Whenever science returns a confident and univocal answer to a question, Trumping Naturalism enjoins us to accept it. The majority of contemporary philosophers are sympathetic to this sort of position. Indeed, several have endorsed it or something very close to it. Arguments for Trumping Naturalism, however, are scant, the principal one being the Track Record Argument. The argument is based on the fact that in cases of conflict, science has a better track record than non-scientific forms of inquiry such as (...) philosophy. My chapter investigates this argument. I enumerate and assess several objections to the argument, from footling objections to stronger ones. My conclusion is that the Track Record Argument is not as strong as imagined. (shrink)

The usual representation of quantum algorithms is limited to the process of solving the problem. We extend it to the process of setting the problem. Bob, the problem setter, selects a problem-setting by the initial measurement. Alice, the problem solver, unitarily computes the corresponding solution and reads it by the final measurement. This simple extension creates a new perspective from which to see the quantum algorithm. First, it highlights the relevance of time-symmetric quantum mechanics to quantum computation: the problem-setting and (...) problem solution, in their quantum version, constitute pre- and post-selection, hence the process as a whole is bound to be affected by both boundary conditions. Second, it forces us to enter into relational quantum mechanics. There must be a representation of the quantum algorithm with respect to Bob, and another one with respect to Alice, from whom the outcome of the initial measurement, specifying the setting and thus the solution of the problem, must be concealed. Time-symmetrizing the quantum algorithm to take into account both boundary conditions leaves the representation to Bob unaltered. It shows that the representation to Alice is a sum over histories in each of which she remains shielded from the information coming to her from the initial measurement, not from that coming to her backwards in time from the final measurement. In retrospect, all is as if she knew in advance, before performing her problem-solving action, half of the information that specifies the solution of the problem she will read in the future and could use this information to reach the solution with fewer computation steps. This elucidates the quantum computational speedup in all the quantum algorithms examined. (shrink)

It is an observed fact that human populations differ in genetic composition. Some of the inherited diversity is due to combined effects of many genes. Although it would be interesting to know the magnitude and nature of the genetic contribution to some characters under polygenic control, such as intelligence or physique, environmental effects may be so great that no genetic analysis is possible—as Thoday has pointed out earlier in this symposium. With other polygenic characters, such as skin colour, the genetic (...) component is more obvious but still difficult to analyse precisely. The number of genes involved, their frequency and dominance have not been established. This is one of the reasons why selective effects on such characters are not readily measured, although they probably exist. (shrink)