I want, in this paper, to expound 'the implication fragment' of a new propositional logic -a logic akin to the currently accepted one, but, unlike it in certain fundamental respects. There are certain questionable theses in current propositional logic -for instance 'P . F D Q' and 'P D (P D Q)' -and this new logic will lack them.
But this new logic may very well be an old one. I came to it through considering what Aristotle's propositional logic might have been, and I would claim that the new logic was a fair enough reconstruction of the propositional logic Aristotle had in mind in his work on the Syllogistic, even if he did not make it explicit. The reasoning for this is admittedly oblique, but it is, I think, sufficiently conclusive; it is as follows. There is a well-known isomorphism between current propositional logic and the logic of (monadic) predicates -both are forms of Boolean Algebra. But Aristotle's predicate logic differs from current predicate logic in certain fundamental respects, hence, parallel with that there will be a propositional logic differing from the current one in a similar way. I say this propositional logic was Aristotle'sit is certainly the only one which could fairly be attributed to him -and this will be supported with reference to one or two things Aristotle did say, explicitly, on the subject.
As regards the presentation of the newfold logic, I shall explain its rationale in connection with some remarks about certain 19th century logicians -Boole, Jevons, Venn, etc. This is for three reasons. First, it was during the 19th century that Aristotelian Logic came first under attack, so it was then that the reasons for its demise, or disgrace, were live issues, debated on all sides. Secondly, going with this, these were the formative years when current propositional logic was being put together, so Chat, again, issues were being debated then which few would raise today. But thirdly, and perhaps most importantly, there is a certain element in the style of nineteenth-century Philosophical Studies 36 (1979) 35-49.