General relativity is commonly thought to imply the existence of a unique metric structure for space-time. A simple example is presented of a general relativistic theory with ambiguous metric structure. Brans-Dicke theory is then presented as a further example of a space-time theory in which the metric structure is ambiguous. Other examples of theories with ambiguous metrical structure are mentioned. Finally, it is suggested that several new and interesting philosophical questions arise from the sorts of theories discussed.

One of the problems of quantum cosmology follows from the fact that the Hamiltonian H of classical general relativity equals zero. Quantizing canonically in the Schrodinger picture, the Schrodinger equation for the wave function Ψ of the universe is therefore the so-called Wheeler-DeWitt equation (where Ĥ is the operator version of H) and we have no quantum dynamics. In particular, it follows directly that, if Ȓ is the operator representing the radius of the universe, where <Ȓ>ψ = Ψ<|Ȓ|>Ψ, for every Ψ. The universe described by (1) does not expand. But worse still is the fact that there is no time development, contrary to our experience. Like a particle in an eigenstate of zero energy, the state of the universe does not change. The still universe resulting from (1) is a manifestation of the more general “problem of time” afflicting canonical quantum gravity. Despite rare claims to the contrary, most consider it to be a serious difficulty for quantum cosmology.

Sober (1992) and Brandon et al. (1994) disagree about the role of screening-off in the appraisal of theories of natural selection. Some problems disregarded by them are unearthed in this discussion note.

In a reply to Nicholas Maxwell, Stein has proved that Minkowski spacetime can leave room for the kind of indeterminateness required both by certain interpretations of quantum mechanics and by objective becoming. By examining the consequences of outcome dependence in Bell-type experiments for the co-determinateness of spacelike-related events, I argue that the only becoming relation that is compatible with both causal and noncausal readings of the quantum correlations is the universal relation. This result might also undermine interpretations of quantum mechanics requiring non-epistemically indeterminate states before measurement and hyperplane-dependent wave collapse.

Paul Teller's (1995) new book, “An Interpretive Introduction to Quantum Field Theory”, is a pioneering work. To the best of our knowledge it is the first book by a philosopher devoted not only to explaining what quantum field theory (QFT) is, but to clarifying the conceptual issues and puzzles to which the theory gives rise (though Auyung 1995 treats some different issues in QFT). As such it is an important book, which we hope will greatly stimulate work in the area as other philosophers and physicists react to it.

The concepts in the title refer to properties of physical theories (which are given, in this paper, a model-theoretic formulation and appropriate idealizations) and this paper investigates their nature and relations. The first three concepts, especially gauge invariance and indeterminism, have been widely discussed in connection to spacetime theories and the hole argument. Since the gauge invariance principle is at the crux of the issue, this paper aims at clarifying the nature of gauge invariance (either in general or as general covariance). I first explore the following chain of relations: gauge invariance => the conservation laws => the Cauchy problem => indeterminism. Then I discuss gauge invariance in light of our understanding of the above relations and the possibility of spontaneous symmetry breaking.

In this paper it is suggested that Freud's ‘tally argument’ (Grünbaum 1984) is not best interpreted as a risky claim concerning the efficacy of psychoanalytic therapy, but as a risky claim concerning the implications of theoretical psychoanalytic explanations of the efficacy of psychoanalytic therapy. Despite the fact that Freud never empirically established that these implications hold, the ‘tally argument’ does draw attention to a critical distinction that is too often neglected in contemporary empirical studies of psychoanalysis and other forms of psychotherapy: between empirical evaluations of the efficacy of psychotherapy and empirical evaluations of theoretical explanations of the efficacy of psychotherapy, and the different forms of comparative enquiry relevant to each. It is argued that the contemporary neglect of this critical distinction, in conjunction with the common negative conception of placebo control treatments in psychotherapy research, has led to the epistemic impoverishment of experimental studies of the various professional psychotherapies. In consequence, although there is good empirical evidence for the efficacy of psychoanalysis and other forms of professional psychotherapy, there is no good empirical evidence for theoretical psychoanalytic explanations of the efficacy of psychoanalysis, or for traditional theoretical explanations of the efficacy of other forms of professional psychotherapy.

There is a widespread impression that General Relativity, unlike Quantum Mechanics, is in no need of an interpretation. I present two reasons for thinking that this is a mistake. The first is the familiar hole argument. I argue that certain skeptical responses to this argument are too hasty in dismissing it as being irrelevant to the interpretative enterprise. My second reason is that interpretative questions about General Relativity are central to the search for a quantum theory of gravity. I illustrate this claim by examining the interpretative consequences of a particular technical move in canonical quantum gravity.

Using Grünbaum 1984 and 1993 as a springboard, Greenwood (this issue) claims to have offered several methodologically salubrious and exegetically illuminating theses on empirical evaluations of theoretical explanations of psychotherapeutic efficacy. According to his exegesis of Grünbaum's construction (1984, Ch. 2, Section C; 1993, 184–204) of Freud's “Tally Argument,” that argument bespeaks a rife neglect of the epistemologically-significant distinction between empirical evaluations of the efficacy of psychotherapy and evaluations of theoretical explanations of that efficacy. Greenwood presents a defense of a qualified version of Popper's critique of psychoanalysis against Grünbaum's objections to it (1984, Ch. 1B). Finally, Greenwood offers a clarification of the concept of a “placebo control” investigation, taking issue with Grünbaum's 1993 (84–87, 91–93).

In the present paper, it is argued contra Greenwood that: (1) his purportedly “best” reading of Freud's Tally Argument and of its import founders, (2) the distinction that Greenwood bemoans as being neglected by mental health researchers actually is a commonplace in the literature on treatment-process and therapeutic outcome, (3) Greenwood's defense of Popper's critique of psychoanalysis is an anachronism, and (4) Greenwood's conceptual analysis of placebo controls is nebulous and misconceived.

Methodological objectivism is a conception of bias which obscures the contingent and limited nature of methodological principles behind the guise of fixed a priori standards. I suggest as an alternative a more flexible view of the operation of bias which I call the attribution model. The attribution model makes explicit the working principles of both parties to an actual charge of bias. It enables those involved to identify the issues in dispute between them, and is the basis for an approach to handling charges of bias within the process of discussion and negotiation which characterizes normal scientific decision-making.

John Greenwood (this issue) claims that neglect of an important methodological distinction has contributed directly to the “epistemic impoverishment” of empirical studies of all forms of professional psychotherapy. I challenge this claim, as well as other important claims he makes about the efficacy of psychoanalysis and other forms of psychotherapy.

Critics of Laudan's normative naturalism have questioned whether methodological rules can be regarded as empirical hypotheses about relations between means and ends. Drawing on Laudan's defense that rules of method are contingent on assumptions about the world, I argue that even if such rules can be shown to be analytic in principle (Kaiser 1991), in practice the warrant for such rules will be empirical. Laudan's naturalism, however, acquires normative force only by construing both methods and epistemic goals as instrumental to practical concerns, and issues only in context-specific and not general methodological principles.