Section 2, The Objective Pull: Society's way of teaching language is by rewarding correct usage and penalizing incorrect usage. This means that in teaching situations the critic must have access to the ground truth. There is variation in how public concepts are, both across concepts and across circumstances within a concept, and this relates to how "objective" the concept is. To learn inductively, instances have to be enough alike that the learner can perform the generalization, and "they have to be enough alike from simultaneous distinct points of view to enable the teacher and learner to share the appropriate occasions." The pull toward objectivity - the latter condition - is a strong pull away from the former, subjective criterion. This is how we achieve uniformity in usage. Yet, we all get there in different ways: "Different persons growing up in the same language are like different bushes trimmed and trained to take the shape of identical elephants" - because the inner branches are completely different.
Section 3, The Interanimation of Sentences: We would not be able to say much if our learning of sentences were only as wholes by direct conditioning or by analogical substitution. Instead, we associate sentences with other sentences. Thus, a "theory as a whole... is a fabric of sentences variously associated to one another and to non-verbal stimuli by the mechanism of conditioned response." It is much like an arch, where blocks are supported by each other and down to the foundation (which in the case of sentences, would be those learned by direct association). When making theoretical conclusions we tend to skip the direct supports via "transitivity of conditioning," in particular sentences that are always true, whether logically or factually. Note that our theories are joined together by sentences as well, and one's entire base of knowledge is tied together in a single larger fabric, though the details of this fabric differ for each individual despite the uniformity in communication.
Section 4, Ways of Learning Words: We can learn words in isolation or contextually as part of sentences (via abstraction), or via description of the intended objects. Substantives, adjectives, and verbs are occasionally learned in isolation. For insensible things we use extrapolation - a form of analogy - to describe them. The more abstruse these things are, the more it is a reciprocal effect: the distinction between using the term to explain the phenomena, and using the phenomena to understand the word, becomes increasingly blurred. Finally, "differences in ways of learning words cut across the grammatical differences and also across the referential ones."
Section 5, Evidence: Generally we need evidence when there is a conflict between the immediate stimuli and the sentences in a theory that project the expected circumstances. We normally bias toward the stimuli, but a strong enough theory enables us to discard data points due to measurement or other failures. This is generally a passive process, but when it is active we tend to seek the simplest story. Even the determination of whether a recognized object is repeated vs. a different very similar object requires this simplicity evaluation. "Whatever simplicity is, it is no casual hobby." Simplicity also usually enhances a theory's scope. Familiarity of principle is another guiding preference when deciding between the evidence and the theory - we try to minimize revisions to a theory that generally makes good predictions. Sufficient reason is another tacit guide: "it is a rejection of the gratuitous."
Section 6, Posits and Truth: "the simplest possible theory to a given purpose need not be unique." Extraordinary things (by this he means the ostensible referents of theoretical terms) are just more vivid and consciously denoted than ordinary things - there is no real difference in their validity on that basis. "We can never do better than to occupy the standpoint of some theory or other." Also, "scientific method is the way to truth, but it affords even in principle no unique definition of truth." Sentences are only meaningful relative to the theory to which they belong - this is how the words and sentences gain their meaning. This is not relativism because we understand our theories in the context of an overall world-theory that delimits how far we can deviate.