about opinion occur. For often men take gall for honey, because a yellow colour is consequent to honey, and since it happens, that the earth when it has rained becomes moist, if it be moist, we think that it has rained, yet this is not necessary. In rhetorical (arguments), the demonstrations which are derived from a sign are from consequent, for when persons desire to show that a man is an adulterer, they assume a consequent, that he is fond of adorning his person, or that he is seen wandering by night, these things, however, are present with many men, but the thing predicated is not present. Likewise, also, in syllogistic (arguments), for instance, the argument of Melissus, that the universe is infinite, assuming the universe to be unbegotten, (for nothing can be generated from what is not,) but what is generated is generated from a beginning; if, therefore, the universe was not generated, it had not a beginning, so that it is infinite. Nevertheless, this does not necessarily happen, for it does not follow, that if whatever is generated has a beginning, whatever has a beginning is also generated, as neither is it necessary, if a man in a fever is hot, that whoever is hot should have a fever.
That which is from what is not a cause, being assumed as a cause, is when what is causeless is taken, as if the elenchus were produced on account of it. Now such a thing happens in syllogisms leading to the impossible, since in these it is necessary to subvert some one of the posita; if then it be reckoned in necessary interrogations, for the impossible to result, the elenchus will often appear to arise on account of this, as that soul and life are not the same, for if generation be contrary to destruction, a certain generation will be to a certain destruction, but death is a certain
