 In Darwin’s wake, theorists have developed formal, quantitative approaches to modeling Darwin’s process. The “focused” usage of natural selection finds its home as an interpretation of a single term in some of these formalisms (and only some of them). Below, we will consider two formal approaches, type recursions and the Price Equation, elements of which have been interpreted as quantifying selection. In the Price Equation, the covariance of offspring number and phenotype is interpreted as quantifying selection; in type recursions, fitness variables (or, equivalently, selection coefficients) are interpreted as quantifying selection. What makes these interpretations focused is that they quantify only a single element of Darwin’s process using the notion natural selection; other facets of Darwin’s process are handled in other ways. So, in type recursions for instance, type frequency variables quantify how the population varies, and “spontaneous” variations are quantified by mutation parameters. Similarly, in the Price Equation, inheritance is captured by a different term than the term that is interpreted as quantifying natural selection. The point is that each formal apparatus as a whole is understood to capture Darwin’s process, while only a single element of that apparatus is said to refer to natural selection.