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 cal way. This comes from the work before us, where it is laid down as the first characteristic of a proposition that it must be either true or false. A distinction, however, is here drawn, for propositions admit the idea of time. Now, it is the case with regard to propositions of past and present time—for instance, “it is raining,” or “it rained yesterday”—that they must either be true or false; but with regard to future propositions this is not the case; for suppose we say “there will be a battle to-morrow between the Turks and Servians”—this may be probable or improbable, but it is neither true nor false. Obviously, there is no existing fact with which to compare such propositions, and thus to pronounce on their truth or falsehood. But it is argued here that if future propositions, or prophecies, could be pronounced to be certainly true, it would do away with human agency and freewill. This may seem hardly worth enunciating, but it was new at the time when this book was written.

The writer, in considering “modal propositions,” which assert things as necessary, probable, or possible, introduces some discussion on “possibility,” and mentions three heads of the possible. Ordinarily, things in this world are first possible, and then become realised, or actual; but there is another class of things which are always actual, and the possibility in them is only latent or implied—such are the “first substances” which have existed from all eternity; and thirdly, there is a class of. things which always seem possible, and yet can never be realised—for instance, the greatest number or the least quantity, which, while we speak of them, no