Psychology and the law have long maintained a collegial relation with one another as adjacent disciplines. In the judicial system, for example, psychologists and psychiatrists are regularly called upon to give evidence concerning the mental status of accused and convicted persons. There is the greater addressee to consider, psychology itself. Psychology meets its other in the court of law. It, too, must integrate what this metaphor mediates for it into a larger, more compendious notion of what it is more deeply about. Without spoiling anything of what is to come, it can already be said that the principal insight that psychology brings to bear upon itself by means of its dreams of the courtroom is that it, too, is to be conceived of as a notional practice, on the one hand, and as a search for truth, on the other. The chapter also presents an overview of the key concepts discussed in this book.