This paper discusses the Einstein-Podolsky-Rosen paradox from a new point of view. In section II, the arguments by which Einstein, Podolsky and Rosen reach their paradoxical conclusions are presented. They are found to rest on two critical assumptions:

1. (a) that before a measurement is made on a system consisting of two non-interacting but correlated sub-systems, the state of the entire system is exactly represented by:

   

2. (b) that the exact measurement of an observable A in one of the sub-systems is possible.

In section III it is shown that assumption (b) is incorrect. Thus we conclude, as did Bohr, that the results of Einstein, Podolsky and Rosen are not valid.

The arguments of section III are quite distinct from Bohr's, and therefore in Section IV this work is related to that of Bohr.

Mr. Sharp's resolution of the Einstein-Podolsky-Rosen paradox is, in my opinion, the right one. However, the resolution does not in my opinion show that “God's in his heaven; all's right with the world (quantum mechanics).” This is in no way a criticism of Sharp; rather, it is inevitable that any resolution of this paradox, dealing as it does with the quantum mechanical concept of “measurement”, must tangle with some of the real difficulties which are lurking in the notion. The purpose of these comments is to use Mr. Sharp's remarks as a basis for bringing out one of the serious conceptual difficulties connected with measurement.

Science is a comparatively recent affair, but the alternatives at our command in philosophy are old ones. The range of Greek philosophy seems to have an astonishing stability. The philosophy of religion was used for centuries to bolster religion. It is some indication of the rapid growth of the prestige of science that now the philosophy of science is used to bolster philosophy.

Factual statements that might qualify for the status of law statements are classed from various philosophically relevant standpoints (referents, precision, structure of predicates, extension, systemicity, inferential power, inception, ostensiveness, testability, levels, and determination categories). More than seven dozen of not mutually exclusive kinds of lawlike statements emerge. Strictly universal and counterfactually powerful statements are seen to constitute just one kind of lawlike statements; classificatory and some statistical laws, e.g., are shown not to comply with the requirements of universality and counterfactual force.

Conditions for lawlike statements to be called laws are then examined, and a liberal criterion of lawfulness is finally proposed, which reads thus: A proposition is a law statement if and only if it is a posteriori (not logically true), general in some respect (does not refer to unique objects), has been satisfactorily corroborated for the time being in some domain, and belongs to a theory (whether adult or embryonic). It is claimed that criteria of laws change alongside with the emergence of new usages of the term ‘law’, and that by adopting a liberal criterion of lawfulness we would conform to contemporary usage and would cease inhibiting the search for regularities in the sciences of man.

Prior to the advent of evolutionary theory the Natural System was generally conceived as based on “distinctions of kind, not consisting in a given number of definite properties” (J.S. Mill). It was considered final and unique, to be arrived at by more than one approach. Evolutionary theory has shifted emphasis to different characters, yet explicitly or implicitly the belief in a final natural system in biology persists in many textbooks and taints research. Allegedly natural systems are shown to be fundamentally arbitrary and artificial, dependent on numerous value judgments and intrinsically conflicting to varying degrees. Because of this and because it has turned into a bar to clear thinking, the adjective “natural” should be abolished.

Although this note is prompted by the recent exchange between Gellner [2], [3] and Needham [4], I shall ignore the issues raised by Gellner's specification for an ideal language. I am concerned here only with Needham's statement that ‘biology is one matter and descent is quite another, of a different order’ which, it will be remembered, Gellner treats as Needham's first error. I write under a sense of obligation, for I discussed this matter with Gellner in 1955 while he was preparing his first article and my arguments then were phrased similarly to those advanced by Needham. It appears that I did not make myself clear to Gellner and I shall try again. I do not wish to attack or defend either protagonist; each is quite able to look after himself. Therefore I propose neither to examine where they have misunderstood each other, nor to discuss the difference between kinship (Gellner's starting-point) and descent (Needham's), but simply to state the connexion, as I see it, between physical and social kinship.

Criticism of the deductive model of explanation continues. In a recent article, “Truisms as the Grounds for Historical Explanations,” Professor Michael Scriven hangs a great many critical points from the distinction between explanations and their justifications. I should like to examine his proposal with a view to showing that in so far as this distinction can be made, it cannot be used as a basis of criticisms of the deductive or covering law model, as it was originally outlined by Professor Carl G. Hempel.