Hence a judgement of this kind has only private validity- is only valid for the individual who judges, and the holding of a thing to be true in this way cannot be communicated. Persuasion, accordingly, cannot be subjectively distinguished from conviction, that is, so long as the subject views its judgement simply as a phenomenon of its own mind. If we can, in addition to this, develop the subjective causes of the judgement, which we have taken for its objective grounds, and thus explain the deceptive judgement as a phenomenon in our mind, apart altogether from the objective character of the object, we can then expose the illusion and need be no longer deceived by it, although, if its subjective cause lies in our nature, we cannot hope altogether to escape its influence. I can only maintain, that is, affirm as necessarily valid for every one, that which produces conviction. Opinion is a consciously insufficient judgement, subjectively as well as objectively.
Belief is subjectively sufficient, but is recognized as being objectively insufficient.
Knowledge is both subjectively and objectively sufficient. I need not dwell longer on the explanation of such simple conceptions. Moreover, the law of such a connection must be certain. For if, in relation to this law, I have nothing more than opinion, my judgement is but a play of the imagination, without the least relation to truth. In the judgements of pure reason, opinion has no place.