syllogism, just as when the terms are universal, but the demonstration is the same as before. Now when the major is universal, simple, and not contingent, but the other (the minor) particular and contingent, if both propositions be assumed affirmative or negative, or if one be affirmative and the other negative, there will always be an incomplete syllogism, except that some will be demonstrated per impossibile, but others by conversion of the contingent proposition, as in the former cases. There will also be a syllogism, through conversion, when the universal major signifies simply inesse, or non-inesse, but the particular being negative, assumes the contingent, as if A is present, or not present, with every B, that B happens not to be present with a certain C; for the contingent proposition B C being converted, there is a syllogism. Still when the particular proposition assumes the not being present with, there will not be a syllogism. Now let the terms of presence be "white," "animal," "snow," but of not being present "white," "animal," "pitch," for the demonstration must be assumed through the indefinite. Yet if the universal be joined to the less extreme, but particular to the greater, whether negative or affirmative, contingent or pure, there will by no means be a syllogism, nor if particular or indefinite propositions be assumed, whether they take the contingent, or simply the being present with, or vice versâ, will there thus be a syllogism, and the demonstration is the same as before; let however the common terms of being present with from necessity be "animal," "white," "man;" and of not being contingent "animal," "white," "garment." Hence it is evident, that if the major be universal, there is always a syllogism, but if the minor be so, (if the major be particular,) there will never be.
Chapter 16
When one is a necessary proposition simple, de inesse, or non-inesse, and the other signifies being contingent, there will be a syllogism, the terms subsisting similarly, and it will be perfect when
