" In the early days of genetics, a gene could be 'dominant' or 'recessive', and that was about all there was to it; but gradually more and more terms had to be added to the vocabulary: repressors, apo-repressors, co-repressors, inducers, modifier genes, switch genes, operator genes which activate other genes, and even genes which regulate the rate of mutations in genes. Thus the action of the gene-complex was originally conceived as the unfolding of a simple linear sequence like that on a tape-recorder or the Behaviourist's conditioned-reflex chain; whereas it is now gradually becoming apparent that the genetic controls operate as a self-regulating micro-hierarchy, equipped with feedback devices which guide their flexible strategies. This not only protects the growing embryo against the hazards of ontogeny; it would also protect it against the evolutionary hazards of phylogeny, or random mutations in its own hereditary materials-the blind antics of the monkey at the typewriter. "

― Arthur Koestler , The Ghost in the Machine