In Foundations of the Theory of Signs (p. 6), the three terms in question were defined follows: pragmatics as the study of "the relation of signs to … - Charles W. Morris

The Encyclopedia presents a contemporary version of the ancient encyclopedic ideal of Aristotle, the Scholastics, Leibniz, the Encyclopedists, and Comte.

According to mead, the primary phenomenon out of which language in the full human sense emerges is the gesture, especially the vocal gesture. The gesture sign (such as a dog's snarl) differs from such a nongestural sign as thunder in the fact that the sign vehicle is an early phase of a social act and the designatum a later phase of this act (in this case the attack by the dog). Here one organism prepares itself for what another organism - the dog - is to do by responding to certain acts of the latter organism as signs; in the case in question the snarl is the sign, the attack is the designatum, the animal being attacked is the interpreter, and the preparatory response of the interpreter is the interpretant.

I share the conviction held by many others that the movement of thought called "symbolism" is of great significance. Not only does this movement cut across the traditional lines of division among philosophers, but it coordinates in a remarkable way the work of linguists, sociologists, psychologists, anthropologists, and biologists, in so far as their work connects with the topic of mind. In the degree that the symbolic movement is significant, a work which develops systematically the basis of the movement, and at the same time applies this analysis to the topic of mind and to certain basic philosophical problems, can at least claim to be an important contribution to critical thought. Whether the claim is substantiated depends, of course, on the quality of the work itself.