 As will be discussed further below, much of the twentieth century was marked by debates among biologists about the relative importance of drift and selection in evolution. Were those debates at least in part the result of conceptual unclarity? Millstein (2002) argues that we need not accept this inadvertent consequence of Beatty’s argument, and that selection can, in fact, be distinguished from drift. In order to do this, three extensions should be made to Beatty’s account. First, similar to Hodge (1987), Millstein suggests that a proper distinction between drift and selection relies on causation, specifically, that drift processes are indiscriminate sampling processes in which any heritable physical differences between entities (organisms, gametes, etc.) are causally irrelevant to differences in reproductive success, whereas natural selection processes are discriminate sampling processes in which any heritable physical differences between entities (organisms, gametes, etc.) are causally relevant to differences in reproductive success. These more precise characterizations of “indiscriminate sampling” and “discriminate sampling” are intended to replace the metaphorical “sampling” talk, retaining the term “sampling” as a useful shorthand only. Second, we should be careful to distinguish the process of drift from the outcomes that drift produces, and the process of selection from the outcomes that selection produces. (Of course, the importance of distinguishing process from outcome is not a novel insight; what is novel here is its application to the problem of distinguishing drift from selection. The distinction has sometimes been rendered as “process vs. product” rather than “process vs. outcome” in the philosophical literature, but given the teleological and other misleading connotations of “product”, the term “outcome” is preferable and “product” should be avoided). Third, we should characterize drift and selection as processes rather than outcomes (as in the first of the three points). If we do these three things, then drift and selection are conceptually distinct and the problem Beatty raises is dissolved; discriminate sampling processes where unlikely outcomes obtain are still selection processes. On this view, it is further acknowledged that it is possible for drift and selection to produce the same outcomes, which helps explain the persistence of biologists’ debates over the relative importance of drift and selection without making them seem trivial (see Millstein 2002 for additional discussion of Beatty’s arguments).