Formal implication is usually represented by symbolization such as ‘ φx ⊃ Ψx,’ which may be read, “for all values of ‘x’, φx implies Ψx.” If the values of the variable ‘x’, in ‘φx’ and ‘Ψx’ be ‘x1’ ‘x2’ ‘x3’, etc., then … ‘φx’ formally implies ‘Ψx’ if and only if, whatever values of ‘x’, ‘xn’, be chosen, ‘φxn’ materially implies ‘Ψxn’ …However, this still leaves it doubtful which of two possible interpretations of expressions having the form ‘ φx ⊃ (...) Ψx’ is to be taken as correct. … It means one thing to say, “Every existent having the property φ … has also the property Ψ,” and it means quite a different thing to say, “Every thinkable thing which should have the property φ must also have the property Ψ.” The second of these holds only when having the properly φ logically entails having the property Ψ; when ‘Ψx’ is deductible from ‘φx’. … The first of them, however, holds not only in such cases … but also in every case where among existent things, one property is universally accompanied by another. (shrink)

One thing that would profit both the frustrated readers of Sellars and Sellars himself would be a careful attempt to explicate and evaluate critically the many interrelated theses stated and defended by Sellars. But, so far as I know, there has been little work of this kind done. I know only of two fine reviews by Keith Lehrer and Gilbert Harman, and a very helpful expository article by Richard Bernstein that deal directly and in some detail with Sellars' work. This (...) is not to mention, however, the many philosophers, including myself, who have been influenced by his work. What I believe would be most helpful at this point would be a critique of some central thesis in Sellars' work, that is, an attempt to raise objections to this thesis and to refute the replies that can be anticipated, based upon other of Sellars' claims. This is what I shall try to do in this paper. My hope is that it will further the understanding of his complex philosophy, and help carry forward discussion of the philosophical issues involved. (shrink)