"Language is Sermonic"

This is a famous essay by Richard M. Weaver. Some selected passages:

the course itself [i.e. rhetoric, aka, I guess, freshman composition] has been allowed to decline from one dealing philosophically with the problems of expression to one which tries to bring below-par students up to the level of accepted usage.

the most obvious truth about rhetoric is that its object is the whole man.  It presents its arguments first to the rational part of man, because rhetorical discourses, if they are honestly conceived, always have a basis in reasoning.  Logical argument is the plot, as it were, of any speech or composition that is designed to persuade.

Rationality is an indispensable part to be sure, yet humanity includes emotionality, or the capacity to deal and suffer, to know pleasure, and it includes the capacity for aesthetic satisfaction, and, what can be only suggested, a yearning to be in relation with something infinite.  This last is his religious passion, or his aspiration to feel significant and to have a sense of belonging in a world that is productive of much frustration. These at least are the properties of humanity.

When we think of rhetoric as one of the arts of civil society (and it must be a free society, since the scope for rhetoric is limited and the employment of it constrained under despotism) we see that the rhetorician is faced with a choice of means in appealing to those whom he can prevail upon to listen to him.  If he is at all philosophical , it must occur to him to ask whether there is a standard by which the sources of persuasion can be ranked.  In a phrase, is there a preferred order of them, so that, in a scale of ethics, it is nobler to make use of one sort of appeal than another?  This is of course a question independent of circumstantial matters, yet a fundamental one.  We all react to some rhetoric as “untruthful” or “unfair” or “cheap,” and this very feeling is evidence of the truth that it is possible to use a better or a worse style of appeal.  What is the measure of the better style?  Obviously this question cannot be answered at all in the absence of some conviction about the nature and destiny of man.  Rhetoric inevitably impinges upon morality and politics; and if it is one of the means by which we endeavor to improve the character and the lot of men, we have to think of its methods and sources in relation to a scheme of values.

every use of speech, oral and written, exhibits an attitude, and an attitude implies an act. 

The implication of all this seems to be that it is not just advisable but essential and fundamental to rhetoric to study the philosophy of human nature, ethics, logic, and philosophy of language. The rest might be studying the techniques of great writers (and maybe some artists, film-makers, etc.), and probably some psychology too. And I don't really see what would be left to cover, other than more philosophy, more literature, etc., plus plenty of practice in persuasive writing, speaking, and so on. It sounds pretty good to me. And a far cry from some of the things I've heard about rhetoric.