I think I have thus sufficiently answered these questions--namely, if a true idea is distinguished from a false idea, only in so far as it is said to agree with its object, a true idea has no more reality or perfection than a false idea (since the two are only distinguished by an extrinsic mark); consequently, neither will a man who has a true idea have any advantage over him who has only false ideas. Further, how comes it that men have false ideas? Lastly, how can anyone be sure, that he has ideas which agree with their objects? These questions, I repeat, I have, in my opinion, sufficiently answered. The difference between a true idea and a false idea is plain: from what was said in II. xxxv., the former is related to the latter as being is to not-being. The causes of falsity I have set forth very clearly in II. xix. and II. xxxv. with the note. From what is there stated, the difference between a man who has true ideas, and a man who has only false ideas, is made apparent. As for the last question--as to how a man can be sure that he has ideas that agree with their objects, I have just pointed out, with abundant clearness, that his knowledge arises from the simple fact, that he has an idea which corresponds with its object--in other words, that truth is its own standard. We may add that our mind, in so far as it perceives things truly, is part of the infinite intellect of God (II. xi. Cor.); therefore, the clear and distinct ideas of the mind are as necessarily true as the ideas of God. XLIV. It is not in the nature of reason to regard things as contingent, but as necessary. >>>>>Proof--It is in the nature of reason to perceive things truly (II. xli.), namely (I. Ax. vi.), as they are in themselves--that is (I. xxix.), not as contingent, but as necessary. Q.E.D. <<<<<Corollary I--Hence it follows, that it is only through our imagination that we consider things, whether in respect to the future or the past, as contingent.