The distinction between discovery and justification is ambiguous. This obscures the debate over a logic of discovery. For the debate presupposes the distinction. Real discoveries are well established. What is well established is justified. The proper distinctions are three: initial thinking, plausibility, and acceptability. Logic is not essential to initial thinking. We do not need good supporting reasons to initially think of an hypothesis. Initial thoughts need be neither plausible nor acceptable. Logic is essential, as Hanson noted, to both plausibility (...) and acceptability. An hypothesis needs good supporting reasons to be either plausible or acceptable. Such reasons need not be relative to the particular scientific theory undergoing test at the time. There is no fundamental difference between reasons relevant to plausibility and acceptability. The difference is one of degree. Acceptability requires more than plausibility. (shrink)

Based on author's dissertation--Yale University.

Feyerabend claims that what is perceived depends upon what is believed ; and he maintains that among really efficient alternative theories "each theory will possess its own experience, and there will be no overlap between these experiences". According to Feyerabend "scientific theories are ways of looking at the world; and their adoption affects our general beliefs and expectations, and thereby also our experiences...". Toulmin, Hanson, and Kuhn concur with this view. Toulmin claims that men who accept different "ideals" and "paradigms" (...) will see different phenomena. He thinks theories not only give significance to facts, but also determine what facts are for us at all. Like Feyerabend, Toulmin asserts that "we see the world through" our fundamental concepts of science "to such an extent that we forget what it would look like without them". Indeed, both Feyerabend and Toulmin would have previous thinkers "live in an observational world very different from our own". Kuhn expresses quite similar views. He feels that. (shrink)

In this article I discuss the justification of scientific change and argue that it rests on different sorts of invariance. Against this background I consider notions of observation, meaning, and regulative standards. I sketch an account of the rationale of scientific change which preserves the merits and avoids the shortcomings of the approach of Feyerabend, Hanson, Kuhn, Toulmin, and others. Each of these writers would hold that transitions from one scientific tradition to another force radical changes in what is observed, (...) in the meanings of the terms employed, and in the metastandards involved. They would claim that "incommensurable" replacement is what does, and should, occur during scientific "revolutions." Such writers, however, have trouble in comparing different scientific theories. My account permits different theories to be compared in various ways. These comparisons, I argue, are possible through appeal to "first-level" and "second-level" invariance. In this connection I argue that observation, meaning, and regulative standards should be, and in fact usually are, nontrivially invariant with respect to scientific change. (shrink)

There is a strong mystical strain running through the Neo-Platonic tradition. It arises from the claim that the One is absolutely transcendent, beyond all thought and all being, ineffable and incomprehensible. This claim readily appears in the doctrines of Plotinus, Iamblichus, and Damascius. It is, however, most carefully dealt with and receives its most systematic espousal from the celebrated Proclus of Athens. Proclus’ Commentary On The Parmenides is a polished espousal of the first hypothesis of Plato’s Parmenides. It is there (...) that he expresses his own view of the One and shows his acute sensitivity to logical problems arising from it. It will be my attempt here to examine the tenability of Proclus’ view of the One. In the course of this examination I will evaluate some of his solutions to the logical difficulties resulting from his position as to the One. I wish to argue that his position is beset with insurmountable difficulties and that his solutions to them are unsatisfactory. (shrink)

Pseudo-appeals to conscience stress that the dictates of conscience are always either morally obligatory or at least not morally wrong. These appeals are untenable. They result in an indefensible moral relativism. They should be abandoned.