This chapter explores the central proposition that the emotion-processing mind has not only evolved over time in accordance with the Darwinian principles of evolution, but, as a cognitive module of the mind, it operates and adapts on a day-to-day basis in significant ways according to the same evolutionary principles. The central theorem of mental Darwinism is that the emotion-processing mind possesses in-built, genetically determined attributes and adaptive capacities—it is not a tabula rasa. Environmental events select from these capacities the most optimal responses to their impingements and cause the preferential reproduction of these favourable adaptive reactions. Instruction is essentially a Lamarckian theory that states that an organism’s learning and adapting occurs strictly through instructions and directives from the environment. The organism is a tabula rasa with vague, if any, potentials, and the environment directs the organization of these potentials into an adaptive response. Selection, which is at the heart of Darwinian theory operates very differently.