In the last ten pages of the book, Freud sets out to "correct some misconceptions" about the theory he has just developed, in order to make sure that his ideas are coming through clearly.
First, Freud clarifies that although it might have seemed as though he was talking about two psychical "systems" in the previous section, what he was really talking about was "two kinds of processes of excitation or modes of its discharge" (7.7.1).
With this in mind, Freud also repeats that when he speaks of the unconscious, the preconscious, and the conscious, he isn't actually speaking of three different "localities" in the mind. Although his language suggests that thoughts move from one place to another, he urges readers to resist thinking of these processes in spatial terms.
Instead, Freud encourages readers to think of them in terms of energy currents. As he says, what he wants to do is "replace a topographical way of presenting things with a dynamic one" (7.7.1).
Having made these clarifications, Freud moves on to consider his theory in light of contemporary psychological research. Specifically, he considers his methods in relation to turn-of-the-century psychological thinking about the unconscious.
Here, Freud makes a startling argument: "The unconscious is the true psychical reality; in its innermost nature it is as much unknown to us as the reality of the external world, and it is as incompletely presented by the data of consciousness as is the external world by the communications of our sense organs" (7.7.4).
Freud also clarifies that it is more correct to think of "two kinds of unconscious": the system Ucs. (the unconscious) and the system Pcs. (the preconscious). He repeats that although the preconscious is different from the unconscious, it is not itself fully conscious, either; rather, it "stands like a screen between the system Ucs. and consciousness" (7.7.7).
Freud continues to clarify the ways in which these systems interact and are regulated. He argues that not only can censorship be present in the relationship between the unconscious and the preconscious, but it can also be present in the relationship between the preconscious and the conscious (7.7.12).
Freud supports this conclusion with two examples from his work with "hysterical" patients. One of them was a young girl who seemed to be having symptoms of a sexual nature, though without any apparent knowledge of sexual matters (7.7.13). The other was a young boy who suffered from "hysterical vomiting, headaches, etc.," which Freud traced to feelings of "suppressed rage against his father" combined with feelings of shame for earlier masturbatory fantasies (7.7.14).
Freud draws the section to a close by affirming once again that the interpretation of dreams has important contributions to make to psychological knowledge.
Freud also anticipates readers' questions about what other kinds of contributions his methods might make to knowledge and society. For example, he asks whether the "ethical significance" of dreams should be considered. After all, if suppressed wishes can lead to dreams, might they "some day lead to other things?" (7.7.15).
Freud says that he doesn't "feel justified" in tackling questions of ethics, but he offers his opinion nonetheless.
In Freud's view, we should "acquit dreams"—which is to say that dreamers shouldn't be held accountable for the unconscious wishes that emerge while they sleep. Freud says that just because a man dreams that he has murdered an Emperor, that doesn't mean that he actually intends to do it in real life (7.7.16).
In the final paragraph of the book, Freud ends by reiterating that dreams can't foretell the future. Rather, he says that "[i]t would be truer to say instead that they give us knowledge of the past" (7.7.18).