In this paper, the author presents his arguments to Fox's premise that functional contextualism has an implications for designing instruction. Fox argues that functional contextualism is an alternative to constructivism because constructivism has not empirically demonstrated its effectiveness. However, the author finds this assertion troubling for several reasons. First, the effects of constructivism are not obvious because constructivism is not a theory of learning. Second, even though constructivism is not a design method, there are numerous reports that empirically validate the ability of innovations based on a constructivist epistemology, such as anchored instruction, problem-based learning, microworlds, cognitive tools, and simulations, to engage and support meaningful learning. Third, if empirical validation were a truth criterion for all theories of learning and models of instruction, most would fail. Fourth, there are other theories that may accomplish the goals of functional contextualism as well as or better than functional contextualism. Fifth, and perhaps most importantly, there is no best model of instruction or theory of learning.