Neuroscience, Psychology, Reduction, and Functional Analysis

The pressure for reduction in science is an artifact of what we call the nomic conception of science (NCS): the idea that the content of science is a collection of laws, together with the deductive-nomological model of explanation. NCS in effect identifies explanation with reduction, thus making no room for the explanatory autonomy of function-analytical explanations. When we replace NCS with something more descriptively accurate, however, we find that the kind of explanatory autonomy of functional-analytic explanations is ubiquitous in the sciences. Key to showing this is a distinction between horizontal and vertical explanation. Horizontal explanations explain the capacities of a complex system by appeal to the design of the system. Vertical explanations, by contrast, explain how a design is implemented in a system. We argue that the distinction between horizontal and vertical explanations provides us with a better picture of the relationship between functional analysis and mechanistic explanation.