 It is important to note that standard etiological theories do not entail that all functions are directly grounded in processes of natural selection operating over an evolutionary span of time. Millikan (1984) offers a theory on which functions can also result from meme selection. Papineau (1984) speaks of learning and Dretske (1986) invokes functions that depend on recruitment by conditioning. Garson (2011, 2019a) argues that the notion of selection should be loosened so that differential retention without differential replication could count as selection, in which case neural selection would qualify as a form of selection that could underwrite content-determining functions. Finally, Millikan (1984) further suggests that functions of novel items can be derived from the functions of the mechanisms that produce them. While the contents of sensory-perceptual representations might be determined by functions that are directly grounded in processes of natural selection, it is plausible to suppose that the content-determining functions for (most) concepts are grounded in one of the other ways.