My research aims to develop a novel exemplary theory of precedent based on Thomas Aquinas’s theory of practical reason and philosophical anthropology. For this it focuses on two sine qua non requirements that any theory of precedent has to satisfy, namely 1) explaining how it is possible for a legal official to follow and distinguish a precedent and 2) explaining how it is possible for an ordinary citizen to follow and distinguish a precedent. These fundamental precedential practices (hereafter FPPs) have to be soundly explained, otherwise it is not possible to recognise the authoritative and conduct-guiding character of law. The novel theory of precedent that I propose is able to provide a sound account of FPPs. It 1) understands precedent as an example; 2) discloses the real nature of the practice of distinguishing; 3) explains how it is possible for our practical reason to discover legal salience among different facts either perceptually (“spontaneously” or with our “cogitative power”) or deliberatively (“discursively” or with our reason); 4) characterises precedent as an instantiation of what Aquinas calls determinatio; 5) embraces in its own light what is true about the theories of precedent analysed in the first part of my work; and 6) reveals the significance of virtues for the predictability and stability of a precedential legal system. This novel exemplary theory of precedent seeks to recover the classical notions of practical reason and determinatio in legal reasoning and to highlight the relevance of an agent’s character traits and inner senses (“the cogitative power” and memory) for reasoning with precedents.