Causality, in philosophy, relationship of a cause to its effect. The Greek philosopher Aristotle enumerated four different kinds of causes: the material, the formal, the efficient, and the final. The material cause is what anything is made of—for example, brass or marble is the material cause of a given statue. The formal cause is the form, type, or pattern according to which anything is made; thus, the style of architecture would be the formal cause of a house. The efficient cause is the immediate power acting to produce the work, such as the manual energy of the laborers. The final cause is the end or motive for the sake of which the work is produced—that is, the pleasure of the owner. The principles that Aristotle outlined formed the basis of the modern scientific concept that specific stimuli will produce standard results under controlled conditions. Other Greek philosophers, particularly the 2nd century skeptic Sextus Empiricus, attacked the principles of causality/