Jowett: Theaetetus 187a-200d — Se o saber não é sensação, talvez seja opinião verdadeira

Soc. But the original aim of our discussion was to find out rather what knowledge is than what it is not ; at the same time we have made some progress, for we no longer seek for knowledge, in perception at all, but in that other process, however called, in which the mind is alone and engaged with being.

Theaet. You mean, Socrates, if I am not mistaken, what is called thinking or opining.

Soc. You conceive truly. And now, my friend, Please to begin again at this point ; and having wiped out of your memory all that has preceded, see if you have arrived at any clearer view, and once more say what is knowledge.

Theaet. I cannot say, Socrates, that all opinion is knowledge, because there may be a false opinion ; but I will venture to assert, that knowledge is true opinion : let this then be my reply ; and if this is hereafter disproved, I must try to find another.

Soc. That is the way in which you ought to answer, Theaetetus, and not in your former hesitating strain, for if we are bold we shall gain one of two advantages ; either we shall find what we seek, or we shall be less likely to think that we know what we do not know — in either case we shall be richly rewarded. And now, what are you saying ? — Are there two sorts of opinion, one true and the other false ; and do you define knowledge to be the true ?

Theaet. Yes, according to my present view.

Soc. Is it still worth our while to resume the discussion touching opinion ?

Theaet. To what are you alluding ?

Soc. There is a point which often troubles me, and is a great perplexity to me, both in regard to myself and others. I cannot make out the nature or origin of the mental experience to which I refer.

Theaet. Pray what is it ?

Soc. How there can be — false opinion — that difficulty still troubles the eye of my mind ; and I am uncertain whether I shall leave the question, or over again in a new way.

Theaet. Begin again, Socrates, — at least if you think that there is the slightest necessity for doing so. Were not you and Theodorus just now remarking very truly, that in discussions of this kind we may take our own time ?

Soc. You are quite right, and perhaps there will be no harm in retracing our steps and beginning again. Better a little which is well done, than a great deal imperfectly.

Theaet. Certainly.

Soc. Well, and what is the difficulty ? Do we not speak of false opinion, and say that one man holds a false and another a true opinion, as though there were some natural distinction between them ?

Theaet. We certainly say so.

Soc. All things and everything are either known or not known. I leave out of view the intermediate conceptions of learning and forgetting, because they have nothing to do with our present question.