_Philosophy and Argument_ presents systematic analysis of the role of argumentation in philosophy.

The purpose of this note is to present a set of rules for the syllogism which not only is equivalent with the set ordinarily used, but also is the dual of the latter. It must be emphasized, however, that the discussion of both of these sets presupposes the hypothetical interpretation of universal propositions, and would not hold true of the existential interpretation of such propositions. A universal proposition is interpreted hypothetically, rather than existentially, when it is not assumed that the (...) class denoted by its subject must have members. Thus the hypothetical interpretation of “All unicorns are mammals” would be just “If anything is a unicorn, then it is a mammal—but it is not necessarily true that unicorns exist.” One important consequence of the distinction between these two modes of interpretation is that rule 3, below, is true for the hypothetical interpretation, but not for the existential. (shrink)

An analysis of effectiveness of some of hume's arguments in a framework developed by the author. The author states his position that arguments attacking positions attempt to show that, Given the assumptions of a position, Certain consequences are incompatible with it--A valid species of "argumentum ad hominem". Although this species does not work for constructive philosophical "proofs," it will work inversely in arguments (defending such proofs) which cite possible objections. These charge "petitio": the objection assumes what the position denies or (...) "vice versa". Eight arguments are judged as "ad hominem" or as charging "petitio" and as effective or ineffective in either case. The analyses elaborate the author's position, And the mode of analysis is suggested as an adjunct to considering a philosopher's conclusions. (shrink)

My chief claim is that no one could understand the meaning of either 'consciousness' or 'unconsciousness' unless his consciousness had been interrupted on at least one occasion. I consider various attempts that might be made to teach the meanings of these terms to a person who had never lost consciousness, And I show how these attempts fail. The ideas of consciousness and unconsciousness can occur only to a person in whose experience there has been a gap.

If necessity is a generic notion, then, like any generic notion, it becomes specified not by a criterion as such but by a differentia. The differentia of logical necessity is that the denial of a logically necessary proposition is self-contradictory; one of our best criteria of logical necessity is that after careful consideration we see that the denial of the proposition is self-contradictory.