According to Habermas, the phenomena that need to be accounted for by the theory are the "intuitively mastered rules for reaching an understanding and conducting argumentation", possessed by subjects who are capable of speech and action.
The result of the theory is a conception of reason that Habermas sees as doing justice to the most important trends in twentieth century philosophy, while escaping the relativism which characterizes postmodernism, and also providing necessary standards for critical evaluation.
Additionally, there are strict limits which a "post-metaphysical" theory (see below) must respect – namely the clarification of procedures and norms upon which our public deliberation depends.
[3] There are a number of specific trends that Habermas identifies as important to twentieth century philosophy, and to which he thinks his conception of communicative rationality contributes.
[4] These post-metaphysical philosophical movements have, among other things: Habermas' conception of communicative rationality moves along with these contemporary currents of philosophy.
On (3) and (4), Habermas's entire conceptual framework is based on his understanding of social interaction and communicative practices, and he ties rationality to the validity basis of everyday speech.
The difference is that Habermas explicates the deep structures of reason by examining the presuppositions and validity dimensions of everyday communication, while the relativists focus only on the content displayed in various concrete standards of rationality.
What this means is that Habermas has, through the formal pragmatic analysis of communication, revealed that rationality should not be limited to the consideration and resolution of objective concerns.
Following Habermas, the argument relies on the following assumptions: From these premises it is concluded that any individual engaging in communication is accountable for the normative validity of the claims they raise.
In its essence the idea of communicative rationality draws upon the implicit validity claims that are inescapably bound to the everyday practices of individuals capable of speech and action.
A mutual understanding can be achieved through communication only by fusing the perspectives of individuals, which requires they reach an agreement (even if it is only assumed) on the validity of the speech acts being shared.
Moreover, the speech acts shared between individuals in communication are laden with three different types of validity claims, all of which quietly but insistently demand to be justified with good reasons.
Thus, the simple process of reaching an understanding with others impels individuals to be accountable for what they say and to be able to justify the validity claims they raise concerning normative (WE), evaluative (I) and objective matters (IT).
Even if it is accepted that rationality must be expanded to include normative and evaluative dimensions, it is not clear what it is that makes a speech act justified, because it is unclear what constitutes a good reason.
The speaker would have to draw on insights into, for instance, the vulnerability of individuals under the weight of life's circumstances, the kinds of rights that humans deserve, etc.
Habermas does suggest some general guidelines concerning the rationality of communicative processes that lead to conclusions (see Universal pragmatics).
The theory of communicative rationality has been criticized for being utopian and idealistic,[5] for being blind to issues of gender, race, ethnicity, and sexuality,[6] and for ignoring the role of conflict, contest, and exclusion in the historical constitution of the public sphere.
[9] Habermas also ignored the hindrances that people may face that may cause a person not to stay educated on the topics in order to participate in communicative rationality.