Published online by Cambridge University Press: 01 January 2020
But as for most genes, they are not the units of interest once we get to the network level: it is the whole conspiracy we care about. (von Dassow and Meir 2003, 27)
Biologists, more precisely evolutionary biologists, and not only psychologists and philosophers also speak of modularity. However the way in which this theoretical construct functions in their discipline is relatively different from the role it obtains in evolutionary psychology and cognitive science. Rather than postulating modules to explain particular traits of organisms, such as the specificity of input systems or limitations of human reasoning abilities, biologists originally simply assume that some form of modularity constitutes a precondition of evolution. They argue that, in order for natural selection to fine tune organisms to their environment, different traits must be able to evolve independently from one another. This implies modularity in one form or another. Organisms will only be able to adapt if they do not come all in one piece, so to speak. It must therefore be possible for changes to occur in one characteristic of an animal without those changes having repercussions throughout the whole organism.