Unfit for rule

In the most general term, banausoi is the label for people who earn their living by plying a "craft" that involves the use of the hands. Banausos, however, is not merely a descriptive term, since it invariably marks a person as mercantile and servile. Thus Aristotle places the "banausic" arts in the category of "wealthgetting that involves exchange" and identifies them as a form of "labour for hire". In text from the classical period, the word banausia and its cognate is virtually monopolized by Xenophon, Plato and Aristotle; this language is never used in oratory or comedy (whose authors tend to reflect democratic sentiments).
First of all, aristocratic writers use the term to define a group of people as "by nature" inferior and unfit for participation in politics.

Nay, in ancient times, and among some nations the artisan class (banausoi) were slaves or foreigners, and therefore the majority of them are so now. The best form of state will not admit them to citizenship; but if they are admitted, then our definition of the virtue of a citizen will not apply to every citizen nor to every free man as such, but only to those who are freed from necessary services. The necessary people are either slaves who minister to the wants of individuals, or mechanics and laborers who are the servants of the community (Aristotle, Politics, III,5 - Jowett).

Xenophon too, claims that banausoi should not participate in politics, since they lack the leisure required for participating in civic affairs in a responsible and beneficial manner:

A good suggestion, Critobulus, for the base mechanic (banausic) arts, so called, have got a bad name; and what is more, are held in ill repute by civilised communities, and not unreasonably… Hand in hand with physical enervation follows enfeeblement of soul: while the demand which these base mechanic arts makes on the time of those employed in them leaves them no leisure to devote to the claims of friendship and the state. How can such folk be other than sorry friends and ill defenders of the fatherland? So much so that in some states, especially those reputed to be warlike, no citizen is allowed to exercise any mechanical craft at all (Oec. IV,2 - Dakyns).

Clearly then, banausia is a loaded and highly derogatory term. Note in particular Aristotle's claim that many banausoi were nouveaux riches, i.e. wealthy members of non-aristocratic class (Politics, III,5)… A passage in Nicomachean Ethics offers clear evidence of this point:

The man who goes to excess and is vulgar (banausos) exceeds, as has been said, by spending beyond what is right. For on small objects of expenditure he spends much and displays a tasteless showiness; e.g. he gives a club dinner on the scale of a wedding banquet, and when he provides the chorus for a comedy he brings them on to the stage in purple, as they do at Megara. And all such things he will do not for honour's sake but to show off his wealth, and because he thinks he is admired for these things, and where he ought to spend much he spends little and where little, much (NE IV,2 - Ross).

In this period, then, we find a rhetoric and ideology which set the "truly free" individual in opposition to men who were free in a merely legal and civic sense. The free or "liberal" man, in short, is leisured, educated, independent, and "truly" fir for rule, whereas the "banausic" or "illiberal" individual is slavish, servile, wage-earning, uneducated and unfit for rule…
I have discussed this ideological and political program because it provides the context for the fourth-century discussions of the "free" activity of theoria.

Andrea W. Nightingale. The rhetoric of philosophic "freedom". In: Spectacles of Truth in Classical Greek Philosophy. Cambridge UP, 2004-2006.