something else. Moreover, those are problems also, of which there are contrary syllogisms (for they admit a doubt, whether they are so and so, because of there being credible arguments in both respects). And those about which we have no argument from their being vast, conceiving it difficult to assign their cause, e. g. whether the world is everlasting or not, for any one may investigate such things as these.
Let then problems and propositions be distinguished as we have said: a thesis, on the other hand, is a paradoxical judgment of some one celebrated in philosophy, as that contradiction is impossible, as Antisthenes said, or that all things are moved, according to Heraclitus, or that being is one, as Melissus asserted, for to notice any casual person setting forth contrarieties to (common) opinions is silly. Or (a thesis is an opinion) of things concerning which we have a reason contrary to opinions, as that not every thing which is, is either generated or perpetual, as the sophists declare, since (they say) that a musician is a grammarian, though he is neither generated nor eternal, for this, even if it be not admitted by any one, may appear to be from possessing a reason.
A thesis then is also a problem, yet not every problem is a thesis, since some problems are of such a kind, as that we form an opinion about them in neither way; but that a thesis is also a problem
