"_Philosophical necessity_," says he, "is really nothing else than the FULL AND FIXED CONNEXION BETWEEN THE THINGS SIGNIFIED BY THE SUBJECT AND PREDICATE OF A PROPOSITION, which affirms something to be true. When there is such a connexion, then the thing affirmed in the proposition is necessary, in a philosophical sense, whether any opposition or contrary effort be supposed or no. When the subject and predicate of the proposition, which affirms the existence of any thing, either substance, quality, act, or circumstance, have a full and CERTAIN CONNEXION, then the existence or being of that thing is said to be _necessary_ in a metaphysical sense. And in this sense I use the word _Necessity_, in the following discourse, when I endeavour to prove _that Necessity is not inconsistent with Liberty_." "The subject and predicate of a proposition, which affirms existence of something, may have a full, fixed, and certain connexion several ways." "1. They may have a full and perfect connexion _in and of themselves;_ because it may imply a contradiction, or gross absurdity, to suppose them not connected. Thus many things are necessary in their own nature. So the eternal existence of being, generally considered, is necessary _in itself;_ because it would be in itself the greatest absurdity, to deny the existence of being in general, or to say there was absolute and universal nothing; and as it were the sum of all contradictions; as might be shown, if this were the proper place for it. So God's infinity, and other attributes are necessary. So it is necessary _in its own nature_, that two and two should be four; and it is necessary, that all right lines drawn from the centre to the circumference should be equal. It is necessary, fit, and suitable, that men should do to others, as they would that they should do to them. So innumerable metaphysical and mathematical truths are necessary _in themselves_; the subject and predicate of the proposition which affirms them, are perfectly connected of _themselves_." "2. The connexion of the subject and predicate of a proposition, which affirms the existence of something, may be fixed and made certain, because the existence of that thing is _already_ come to pass; and either now is, or has been; and so has, as it were, made sure of existence. And therefore, the proposition which affirms present or past existence of it, may by this means, be made certain, and necessarily and unalterably true; the past event has fixed and decided the matter, as to its existence; and has made it impossible but that existence should be truly predicated of it. Thus the existence of whatever is already come to pass, is now become necessary; it is become impossible it should be otherwise than true, that such a thing has been."