The possibility of forming structures by a process of replication gives those elements that have the capacity for doing so better chances of multiplying. Those elements will be preferably selected for multiplication that are capable of forming into more complex structures, and the increase of their members will lead to the formation of still more such structures. Such a model, once it has appeared, becomes as definite a constituent of the order of the world as any material object. In the structures of interaction, the patterns of activities of groups are determined by practices transmitted by individuals of one generation to those of the next; and these orders preserve their general character only by constant change (adaptation).
Appendix C, The Fatal Conceit– Hayek