One particular aspect of human life sets our species apart from all others. It is not the way in which we function as a society, care for the weak, wage war on each other or farm the land. Neither does it equate to our education of the young, the desire to explore and conquer, or our perennial resourcefulness through good times as well as bad. Yet it is in every one of these, and much of our remaining behaviour besides.
All species need to know how to behave. Every individual organism, regardless of how basic its physiology or intelligence, requires instructions for living. For nonhuman species, the majority or even all of the data providing these essential facts is inherited genetically. Photosynthesizing phytoplankton thrive where the light is strong because their systems are programmed to do so; many species of dormice conserve energy by hibernating for the same reason, and kittens play instinctively because it helps them to develop their predatory skills. These behavioural traits occur as if spontaneously, and each generation of the species engages in similar activities to the one before. During its lifetime, a conscious organism may employ its memory to help adjust its behaviour according to experience, but can only do so within certain parameters imposed by the underlying genetic code. With minor exceptions, alterations in this inherited information are painstakingly slow and limited in scope, and little happens that is not prescribed by its detail.
Humans, on the other hand, are different. The species still retains its genetically encoded instructions that direct and inform innumerable activities such as sleeping and waking or breathing and eating, but there is a second source of guidance available to the individual. From birth to death we receive more of our behavioural instruction via cultural means than any other species, and it is this ability to process and transmit a