Mead traces the emergence of linguistic forms of communication using as his guideline the step-by-step transformation of obiective or natural meanings of systemically ordered mean-ends relations between observed behavioral responses into the meanings that these modes of behavior take on for the participating organisms themselves. Symbolic meanings arise from a subjectivizing or internalizing of objective structures of meaning. As these structures are mainly found in the social behavior of animals, Mead tries to explain the emergence of language through the fact that the semantic potential residing in gesture-mediated interaction becomes symbolically available to participants through an internalization of the language of gestures. Habermas, The Theory of Communicative Action, Vol 2, p.7-8

Meaning is thus a development of something objectively there as a relation between certain phases of the social act; it is not a psychical addition to that act and it is not an 'idea' as traditionally conceived. A gesture by one organism, the resultant of the social act in which the gesture is an early phase, and the response of another organism to the gesture, are the relata in a triple or three-fold relationship of gesture to first organism, of gesture to second organism, and of gesture to subsequent phases of the given social act; and this three-fold relationship constitutes the matrix within which meaning arises, or which develops into the field of meaning. Mead, Mind, Self and Society, p.76 in Habermas, The Theory of Communicative Action, Vol 2, p.8

Mead illustrates the latter with examples of gesture-mediated interactions between animals belonging to the same species, such as a fight between two dogs. The interaction is set up in such a way that the beginnings of movement on the part of one organism are the gestures that serve as the stimulus eliciting a response on the part of the other; the beginnings of this latter movement become in turn a gesture that calls forth an adaptive response on the part of the first organism: "I have given the illustration of the dog-fight as a method of presenting the gesture. The act of each dog becomes the stimulus to the other dog for his response. There is then a relationship between these two; and as the act is responded to by the other dog, it, in turn, undergoes changes. The very fact that the dog is ready to attack another becomes a stimulus to the other dog to change his own position or his own attitude. He has no sooner done this than the change of attitude in the second dog in turn causes the first dog to change his attitude. We have here a conversation of gestures. Habermas, The Theory of Communicative Action, Vol 2, p.7

In adopting toward themselves the critical attitude of others when the interpretation of communicative acts goes wrong, they develop rules for the use of symbols. They can now consider in advance whether in a given situation they are using a significant gesture in such a way as to give the other no grounds for a critical response. In this manner, meaning conventions and symbols that can be employed with the same meaning take shape. Habermas, The Theory of Communicative Action, Vol 2, p.15

[…] we can specify the transformations that have to take place along the way from gesture-mediated to symbolically mediated interaction. First, gestures are transformed into symbols through replacing meanings that exist for individual organisms with meanings that are the same for both participants. Second, the behavior of participants changes in such a way that an interpersonal relation between speaker and addressee replaces the causal relation between stimulus-response- stimulus in interacting with one another, participants now have a communicative intent. Finally, there is a transformation of the structure of interaction, in that the participants learn to distinguish between acts of reaching understanding and actions oriented to success. The problem of the transition from the stage of gesture-mediated interaction to the stage of symbolically mediated interaction is resolved in these three steps. Habermas, The Theory of Communicative Action, Vol 2, p.9

If S learns to adopt toward himself the negative positions that T, U, V... take toward him when he goes wrong "semantically" (and if T, U, V, for their part, deal with similar disappointments in like manner), the members of this tribe learn to address calls to one another in such a way that they anticipate critical responses in cases where q0 (the expression / utterance) is used inappropriately to the context. And on the basis of this anticipation, expectations of a new type can take shape, behavioral expectations (c) based on the convention that a vocal gesture is to be understood as "g" only if it is uttered under specific contextual conditions. With this we have reached the state of symbolically mediated interaction in which the employment of symbols is fixed by meaning conventions. Participants in interaction produce symbolic expressions guided by rules, that is, with the implicit expectation that they can be recognized by others as expressions conforming to a rule. Habermas, The Theory of Communicative Action, Vol 2, p.22

The use of the same symbols with a constant meaning has to be not only given as such; it has to be know. able for the symbol users themselves. And this sameness of meaning can be secured only by the intersubjective validity of a rule that "conventionally" fixes the meaning of a symbol. In this respect the transition from gesture-mediated to symbolically mediated interaction also means the constitution of rule-governed behavior, of behavior that can be explained in terms of an orientation to meaning conventions. I would like to recall here Wittgenstein's analysis of the concept of a rule […]. In the concept of a rule, the two moments characteristic of the use of simple symbols are combined: identical meaning and intersubjective validity. The generality that constitutes the meaning of a rule can be represented in any number of exemplary actions. […] The concept of rule competence refers not only to the ability to produce symbolic expressions with communicative intent and to understand them; nevertheless it is a key to our problem because we can explain what we mean by the sameness of meaning in connection with the ability to follow a rule […]. “[…] It is not possible to obey a rule privately”: The point of this consideration is that S cannot be sure whether he is following a rule at all if there is no situation in which his behavior is exposed to critique by T - a critique that is in principle open to consensus. Wittgenstein wants to show that the identity and the validity of rules are systematically interconnected. To follow a rule means to follow the same rule in every single case. The identity of the rule in the multiplicity of its realizations does not rest on observable invariants but o n the intersubjectivity of its validity. […] With this analysis of the concept of following a rule, Wittgenstein demonstrates that sameness of meaning is based on the ability to follow intersubjectively valid rules together with at least one other subject; both subjects must have a competence for rule-governed behavior as well as for critically judging such behavior. Habermas, The Theory of Communicative Action, Vol 2, p.16-21

Mead thinks he can explain the genesis of meanings that are the same for at least two participants by one organism internalizing the relation between its own gesture and the response of the other; the internalization comes about through one organism taking up the attitude in which the other responds to its gesture. If this were the case, it would remain only to specify the conditions under which taking the attitude of the other - that is, the process of internalizing objective meaning structures - can get under way. Habermas, The Theory of Communicative Action, Vol 2, p.11