On Sophistical Refutations   

should have the number of considerations on which the fallacious

proofs depend: for they could not depend on more, but all will

depend on the points aforesaid.

A sophistical refutation is a refutation not absolutely but

relatively to some one: and so is a proof, in the same way. For unless

that which depends upon ambiguity assumes that the ambiguous term

has a single meaning, and that which depends on like verbal forms

assumes that substance is the only category, and the rest in the

same way, there will be neither refutations nor proofs, either

absolutely or relatively to the answerer: whereas if they do assume

these things, they will stand, relatively to the answerer; but

absolutely they will not stand: for they have not secured a

statement that does have a single meaning, but only one that appears

to have, and that only from this particular man.



9



The number of considerations on which depend the refutations of

those who are refuted, we ought not to try to grasp without a

knowledge of everything that is. This, however, is not the province of

any special study: for possibly the sciences are infinite in number,

so that obviously demonstrations may be infinite too. Now

refutations may be true as well as false: for whenever it is

possible to demonstrate something, it is also possible to refute the

man who maintains the contradictory of the truth; e.g. if a man has

stated that the diagonal is commensurate with the side of the

square, one might refute him by demonstrating that it is

incommensurate. Accordingly, to exhaust all possible refutations we

shall have to have scientific knowledge of everything: for some

refutations depend upon the principles that rule in geometry and the

conclusions that follow from these, others upon those that rule in

medicine, and others upon those of the other sciences. For the