All students of language concede to it a certain public character. Insofar as it serves in communication, it is a publicly-agreed-upon thing; and when one passes the outer limits of the agreement, one abandons comprehensibility. Now rhetoric affects us primarily by setting forth images which inform and attract. Yet because this setting forth is accomplished through a public instrumentality, it is not free; it is tied more or less closely to the formalizations of usage. The more general and rigid of these formalizations we recognize as grammar, and we shall here speak of grammar as a system of forms of public speech. In the larger aspect, discourse is at once bound and free, and we are here interested to discover how the bound character affects our ability to teach and to persuade. We soon realize that different ways of saying a thing denote different interests in saying it, or to take this in reverse as we do when we become conscious users of language, different interests in a matter will dictate different patterns of expression. Rhetoric in its practice is a matter of selection and arrangement, but conventional grammar imposes restraints upon both of these. All this amounts to saying what every sensitive user of language has sometimes felt; namely, that language is not a purely passive instrument, but that, owing to this public acceptance, while you are doing something with it, it is doing something with you, or with your intention.[117] It does not exactly fight back; rather it has a set of postures and balances which somehow modify your thrusts and holds. The sentence form is certainly one of these. You pour into it your meaning, and it deflects, and molds into certain shapes. The user of language must know how this counterpressure can be turned to the advantage of his general purpose. The failure of those who are careless, or insensitive, to the rhetoric of grammar is that they allow the counter force to impede their design, whereas a perspicacious use of it will forward the design. One cannot, for example, employ just any modifier to stand for a substantive or just any substantive to express a quality, or change a stabilized pattern of arrangement without a change in net effect, although some of these changes register but faintly. But style shows through an accumulation of small particulars, and the artist in language may ponder a long while, as Conrad is said to have done, over whether to describe a character as “penniless” or “without a penny.”