Eudemian Ethics

And about all these matters the endeavor must be made to seek to convince by means of rational arguments, using observed facts as evidences and examples. For the best thing would be if all mankind were seen to be in agreement with the views that will be stated, but failing that, at any rate that all should agree in some way. And this they will do if led to change their ground, for everyone has something relative to contribute to the truth, and we must start from this to give a sort of proof about our views; for from statements that are true but not clearly expressed, as we advance, clearness will also be attained, if at every stage we adopt more scientific positions in exchange for the customary confused statements.

And in every investigation arguments stated in philosophical form are different from those that are non-philosophical; hence we must not think that theoretical study of such a sort as to make manifest not only the nature of a thing but also its cause is superfluous even for the political student, since that is the philosophic procedure in every field of inquiry. Nevertheless this requires much caution.

For because to say nothing at random but use reasoned argument seems to mark a philosopher, some people often without being detected advance arguments that are not germane to the subject under treatment and that have nothing in them

(and they do this sometimes through ignorance and sometimes from charlatanry), which bring it about that even men of experience and practical capacity are taken in by these people, who neither possess nor are capable of constructive or practical thought.

And this befalls them owing to lack of education—for in respect of each subject inability to distinguish arguments germane to the subject from those foreign to it is lack of education.

And it is also well to judge separately the statement of the cause and the demonstrated fact, both for the reason stated just now, that it is not proper in regard to all things to attend to theoretical arguments, but often rather to the facts of observation (whereas now when men are unable to refute an argument they are forced to believe what has been said), and also because often, although the result that seems to have been proved by the arguments is true, it is not true because of the cause asserted in the argument. For it is possible to prove truth by falsehood, as is clear from Analytics.