In the quantum theory the state of an evolving system is represented by a function that depends on time and perhaps on some other parameters. It is generally called the “psi-function”, and it evolves according to an equation called the Schrödinger equation. Indeed Schrödinger introduced the psi-function into physics. In the beginning (i.e., in 1926) Schrödinger thought that the psi-function referred to a fuzzy bit of reality. That is, he pictured an electron, whose state was given by a certain psi-function, as a pulsating bit of electricity, something like an electrical cloud or a patch of electrical fog. In short order, however, Schrödinger saw difficulties with this interpretation, and after trying out more sophisticated refinements he abandoned the whole project. What he abandoned was the program of trying to interpret the psi-function as directly representing some spatiotemporal features of the object whose state it characterized.

There is an interesting problem concerning component causes posed by Cartwright (1983) in her book How the Laws of Physics Lie, which is easily explained in terms of a simple example. Consider a cup sitting on the table. Why doesn’t it move? The explanation given by Newtonian mechanics is that the cup is experiencing two forces-the downward force of gravity and the upward ‘elastic’ force of the table-and these two forces exactly cancel to produce a zero resultant force. This zero resultant force then produces a zero acceleration, which ‘explains’ why the cup doesn’t move. This rather simple, yet typical, example of theoretical explanation raises a surprisingly deep puzzle: What justification is there for believing in the existence of the component forces if they are redundant to the explanation? For it does not really matter what size the component forces are so long as their resultant is zero.

Herbert Feigl was born December 14, 1902 in Reichenberg, Austria, and he died in Minneapolis, Minnesota, on June 1,1988. His wife, Maria, followed him in death on February 13,1989. He is survived by a son, Eric O. Feigl, who is professor of physiology at the University of Washington.

Feigl's parents were Jewish but not religious; indeed, his father was an outspoken atheist. His father was a weaver and later an influential textile manufacturer, who would have preferred the son to become an industrial chemist. His mother was a devotee of the arts and an amateur pianist, who would play Beethoven sonatas over and over at the young son's request. His high school interests were philosophy, science fiction, physics, and chemistry (which was his major). Moritz Schlick became his favorite philosopher after he read the latter's Allgemeine Erkenntnisslehre. His chief intellectual hero was Einstein.

An inexact generalization like ‘ravens are black’ will be symbolized as a prepositional function with free variables thus: ‘Rx ⇒ Bx.’ The antecedent ‘Rx’ and consequent ‘Bx’ will themselves be called absolute formulas, while the result of writing the non-boolean connective ‘⇒’ between them is conditional. Absolute formulas are arbitrary first-order formulas and include the exact generalization ‘(x)(Rx → Bx)’ and sentences with individual constants like ‘Rc & Bc.’ On the other hand the non-boolean conditional ‘⇒’ can only occur as the main connective in a formula. We shall also need to consider formulas with more than one free variable such as ‘xHy ⇒ xTy,’ which might express ‘if x is the husband of y then x is taller than y.’ Though it is inessential, it will simplify things to work in ‘n-languages’ with a finite number of individual constants c1,…, cn, which are interpreted as denoting the elements of the domains of the ‘n-models’ to be described below.

Herbert Feigl was one of the most admirable people I have known. I was fortunate to have him a a friend and as a teacher (he directed my PhD dissertation). He was a very special friend and a very special teacher. To round out what is being said here, I want to share my impressions of him as a teacher and as a person.

I don't think I ever took a course from Herbert; he taught me informally as a thesis director and as a helpful older friend. When he guided me through the writing of my thesis, I was almost unaware fo the teaching he was doing. It is only in recent years that I have come to appreciate how important it was for me.

In comparison with other teachers, Herbert was extremely permissive—the opposite of coercive. For him, nothing was off-limits.

Let's begin with a

Definition: The Anthropic Principle is the drawing of scientific inferences from a consideration of Man's Place in Nature.

There are various versions of the Anthropic Principle. The most conservative version of the Anthropic Principle is nothing but a systematic working out of the fact that the astrophysical (and other scientific) data we have is self-selected due to the fact that Homo sapiens is a particular type of intelligent being. This conservative version of the Anthropic Principle is called the

Again, the Weak Anthropic Principle is just a warning to take into account a grandiose type of selection bias when interpreting data.

In this paper I take Hempel’s raven paradox as the claim that statements of the form ‘∼Ru v Bu’, ‘u is not a raven or u is black,’ confirm the hypothesis h ‘(x)(Rx → Bx)’, ‘All ravens are black.’ Although Hempel discusses this using a criterion of confirmation expressed wholly in terms of deductive logic (see 1965, pp. 35-9), it has become more common to articulate criteria of confirmation using concepts of probability and, in particular, to employ the positive relevance criterion of confirmation which says that, given background knowledge k, (i) e confirms h if and only if P(h/e.k)>P(h/k); (ii) e disconfirms h if and only if P(h/e.k)<P(h/k) and (iii) e is irrelevant to h if and only if P(h/e.k)=P(h/k).

Prof. Tipler and his colleague John Barrow, applying the results and methods of contemporary physics, have made a number of suggestions for pushing beyond the limits of science as ordinarily understood, sometimes suggesting that ideas once thought archaic and worthy to be discarded can be revivified in the light of our new theoretical understanding of the world. The role of the observer in quantum mechanics, they suggest, makes at least plausible “idealist” claims of the dependence of matter on mind. Cosmology, they suggest, provides a framework in which the idea of God as evolutionary endpoint of man-in-nature, familiar from Teilhard de Chardin, can be made concrete and plausible at least as a possibility. All of this, admittedly speculative, structure is presented in something like the form of an inverted pyramid, resting at its base on the much less ambitious, if much more secure, methodological posits of the sort grouped together under the (somewhat misleading) rubric of the “Weak Anthropic Principle.”

D.A. Armstrong’s account (1983, intimately influenced by Tooley 1977 and Swoyer 1982) of natural laws is that they are relations between universals. Armstrong doesn’t simply hold that laws are some relationships or other between universals. He also holds that they are first-order universals themselves (1983, pp. 89-90). Each ordinary law-say, causal law-is numerically identical to some first-order universal. This is a striking, seemingly incredible hypothesis. What is Armstrong thinking of when he says (1983, p. 90):

A commonplace thesis of the “new philosophy of science” is the view that the testing of a given theory is not a simple comparison of the theory with nature but also requires the comparison of the theory with competing theories. More specifically the version of the intertheoretic competition thesis that shall be examined is as follows:

The “hole argument” shows that spacetime substantivalism leads to a radical form of indeterminism in a broad class of spacetime theories. My purpose in this note is twofold. First I shall present a short and informal version of the argument in the form developed in Earman and Norton (1987). Second I will show how the argument can be extended to the case of “manifold plus further structure” substantivalism whenever that further structure admits certain common symmetries.

The hole argument depends on the possibility of displaying two models of some spacetime theory which agree everywhere but within a small neighborhood of the spacetime manifold. To illustrate how two such models are arrived at, I will describe the construction for the easy to visualize special case of a spatially homogeneous and isotropic expanding universe in general relativity. It will be clear how the construction can be extended to other spacetime theories.

With help from Einstein, John Norton and John Earman (1987; this volume) have invented a fascinating argument against spacetime substantivalism. It gives the philosophy of space and time a refreshing stimulus: all credit to them. The idea of the argument is that substantivalism rules out determinism, even of very weak kinds. Norton and Earman have no special brief to defend determinism. But they believe that if it fails, it should fail for reasons of physics that vary from case to case—it should not fail at a stroke for the sake of a philosophical doctrine such as substantivalism. They conclude that in the conflict between substantivalism and determinism, it is substantivalism that must go.

The conflict arises from ‘hole diffeomorphisms’. These enable us, once we are given a model for a spacetime theory, to produce another model.

How do vague notions about how one might understand certain physical phenomena get transformed into scientific concepts such as “field”, “quark”, and “gene”? Philosophers of as disparate views as Reichenbach and Feyerabend have held that the process through which scientific concepts emerge is not a reasoned process. In a manner completely mysterious and unanalyzable, scientific concepts emerge fully grown, like Athena from the head of Zeus. However, when one examines actual cases of concept formation in science, a different picture can be painted: Scientific concepts do not pop out of heads, but are constructed in response to specific problems by utilizing methods appropriate to the solution of the problem. Thus, as with other aspects of the scientific enterprise, concept formation is a problem-solving process that involves the application of systematic procedures in the attempt to solve specific problems. It is a reasoned process.

In recent decades, much work has been directed toward clarifying the logical relations among various sciences. Because of an emphasis on the logical aspects of interfield relations, the issue of scientific unity often wore a distinctly logical mantle.1 For example, Robert Causey, a prominent philosopher of this tradition, has linked scientific unity and progress to a project of successive microreductions. He states, “Other things being equal, we tend to feel that our understanding of a class of phenomena increases as we develop increasingly general and intuitively unified theories of that class of phenomena. It is therefore natural to consider the possibility of one very general, unified theory which, at least in principle, governs all known phenomena.” (1977, p. 1)

Kinds of unity separable from reductive logical unity have, of course, been proposed; these include reductive and nonreductive unities of method, translation, and ontology. For example, J.A. Fodor (1974) has argued for a broad kind of ontological unity of token physicalism, and against type reduction.

The debate over the ontological status of space has been waged over the millennia on many battlefields. In ancient times the major focus was on the possibility of a vacuum, an entity that was both something and yet, in another way, nothing. Newton shifted the scene of action to dynamics, to the question of the ontological commitments needed to give an adequate explanation of observable phenomena. But along with the dynamical effects of Newtonian absolute space came also the spectre of motions unobservable in principle, a notion attacked from Leibniz onward as conceptually absurd or meaningless. So the theater of operation was moved again, especially by verificationists, this time into theories of meaning. Now John Norton and John Earman have opened an entirely new line of assault on the question. They argue that considerations about the possibility of determinism have direct implications for the substantivalist-relationist controversy.