This manner of philosophizing, of disputing all things and assuming nothing certainly, was begun by Socrates, revived by Arcesilaus, confirmed by Carneades, and has descended, with all its power, even to the present age; but I am informed that it is now almost exploded even in Greece.

However, I do not impute that to any fault in the institution of the Academy, but to the negligence of mankind.

If it is difficult to know all the doctrines of any one sect, how much more is it to know those of every sect! which, however, must necessarily be known to those who resolve, for the sake of discovering truth, to dispute for or against all philosophers without partiality.
I do not profess myself to be master of this difficult and noble faculty; but I do assert that I have endeavored to make myself so; and it is impossible that they who choose this manner of philosophizing should not meet at least with something worthy their pursuit.

I have spoken more fully on this head in another place.

But as some are too slow of apprehension, and some too careless, men stand in perpetual need of caution.