Both development and evolution had associated with them the notion of progress (i.e., a process of betterment leading to the achievement of some idealised state). The use of such terms as the development of ‘lower’ and ‘higher’ mental abilities as well as the evolution of ‘lower’ and ‘higher’ organisms contains the assumption of both progress and change. While progress implies change, not all changes are progressive as some developmental change can be regressive and evolutionary change can lead to the extinction of a species. Progress also implies direction. Once again a distinction can be made as, while progress implies direction, the opposite is not necessarily the case. To say that a directional trend in terms of a linear sequence of changes involves improvement such that the end state is somehow better than the initial state requires a value judgment of improvement (e.g., does the directional change from fluid intelligence to a greater reliance on crystallised intelligence identified by life-span developmental psychologists represent ‘betterment’?). A wonderfully articulate critique of the notion of ‘progress’ can be found the recent book entitled The silence of animals:on progress and modern myths (2013) by the political philosopher John Gray.
See Crystallized intelligence, Cultural evolution, Development, Developmental hypothesis, Fluid intelligence, Quantitative and qualitative change, Qualitative and quantitative regressions