Theories of ecological function often appeal to the liberality criterion to evaluate a theory’s adequacy. The liberality criterion requires that a functional description successfully differentiates between functions and nonfunctions. A functional description is considered inadequate if it is excessively liberal or excessively restrictive. I criticize the deference that is shown to the liberality criterion. I present a hypothetical case to illustrate how the application of the liberality criterion needlessly problematizes the four general theories of ecological function. Instead, a theory’s functional description should be considered adequate as long as it produces a better understanding of the complex phenomenon under study.