One of the most basic tools, № 2 pencil test used by any person illustrates the exclusive discretion of the human mind, in comparison with a limited range of animal cognition. Kept painted wood, write and erase a lead with pink rubber retained by a metal ring. Four different materials, each with a specific function, all wrapped into one single instrument. While this tool is made for writing, it can also attach the tail into a bun, tag page or stab one annoying insect. Tools of the animals, unlike chimpanzees, for example rods used to fish termites out of their mounds are composed of one material for one function, and never be used for other functions. There have combinatorial properties of a pencil.
Another simple tool, telescopic, folding cup found in many appliances of camper’s, gives an example of recursion in action. To make this device, the manufacturer need only one simple rule, add a program segment to increase the size of the last segment and it is repeated until the desired size. People use recursive operations such as in almost all aspects of mental life, of language, music and mathematics for the formation of an unlimited range of movements with our feet, hands and mouth. The only glimmerings of recursion in animals, however, come from watching their propulsion systems in action.
