The history of design is a history of evolving problems. The earliest problems were those of practice and production, and the solution of those problems led to further problems of practice and production, as well as problems of philosophy and theory that were consequent upon the existence of new products. In the ancient world, there was little need to distinguish design from the making of products, because the craftsperson and the master-builder carried within themselves both the ability to conceive products and the ability to embody their conceptions in tangible form. Technical treatises were written to solve the problem of education, passing on accumulated knowledge of practice and production to individuals who would continue the work of making. Even before such treatises were written, however, there were already theoretical and philosophical speculations on the nature of products and their effects on human life. Those speculations were typically embedded in treatises on other subjects and problems, but they provided the distant foundations for what is now regarded as the field of design and design research. They characterised the subject matter of human-made products or the artificial, developed the fundamental strategies of inquiry into the nature of products and making, and explored possible principles of making and use that would later turn design from a trade practice into a domain of many professions and, subsequently, into a field of research encompassing history, criticism and theory, supported by empirical research and further philosophic speculation. This field did not emerge in recognisable form until the 20^th century, when the problems of design and technology became so complex that their resolution required new thinking.