Thinkers opposed to the increased dominance of technological progress have continued to express a fear that the result will be disaster or dehumanization. Their opposition to the utilitarian reconfiguration of the idea of progress has been all the more effective because even the technophiles cannot agree on which innovations will gain control of society or on what the results will be. In the absence of a clear-cut goal which progress is supposed to achieve, it is always possible to disagree about the benefits and dangers of what is being developed. As other cultures take up the focus on technological innovation, it is no longer clear that the West will shape the future. Diversity and innovation remain the key factors, just as the Darwinian perspective on progress would imply.

The last step in the ascent of the chain of being was from the apes (considered as the highest animals) to humans. In the eighteenth century the linear model of the chain was applied to this transition by depicting the non-European races as intermediate stages between the apes and the highest human type. Nineteenth-century anthropologists used various characters, especially skull size and shape, to give an appearance of scientific credibility to the supposed racial hierarchy. Early theories of evolution often treated the 'lower' races as relics of earlier stages in the origin of humanity. When evolution was represented as a branching tree, the concept of parallelism was invoked to imply that some branches of humanity had not advanced as rapidly up the scale as others. Europeans' sense of their own racial superiority was thus preserved in the post-Darwinian era by converting the chain of being into an abstract scale of mental development ascended by several forms but at different rates.

Utilitarian thinkers focused not on spiritual development but on the ascent towards a perfectly ordered society in which all could lead a comfortable life. The emergence of more complex societies in the course of history was used by thinkers such as Condorcet to justify the hope of achieving such a society in the future. Opinions differed on the best way to approach the goal. British social theorists followed a model in which free-enterprise individualism gradually threw off the imperfections of less-mature forms of social order. In France, Comte's positivism saw rational planning by experts as the way forward, a position adopted by social planners into the twentieth century. The Marxists, meanwhile, modified Hegel's system of developmental stages to give a more radical vision in which revolution was the only way of achieving the final goal. All of these social thinkers accepted a significant role for technological innovation as a means of improving the human condition, but tended to see industrial development as following a predetermined path.

Applying the Darwinian perspective to human origins required palaeoanthropologists to abandon the assumption that the human race is the goal of the evolutionary process. Darwin himself suggested that our acquisition of higher mental powers was a by-product of an adaptive shift to walking upright. Although rejected for decades, this approach became widely accepted in the 1930s as fossil discoveries confirmed that bipedalism preceded the expansion of the brain and the plausibility of natural selection was boosted by the synthesis with genetics. Most of the biologists who pioneered the synthesis accepted that the human species could no longer be regarded as an inevitable outcome of evolution. Science-fiction authors began to explore the idea that there might be non-human aliens, recognizing that evolution could produce intelligent beings in many different ways.

Historians have recognized parallels between the temporalized chain of being and early ideas about human progress, both being seen as the ascent of a linear scale of development towards a predetermined goal. But the sequence of developmental stages postulated by social thinkers could be defined in different ways depending on whether the goal was a spiritual one (paradise) or a more utilitarian vision of a perfectly ordered society guaranteeing happiness for all (utopia). This chapter outlines the emergence of the more spiritual approach, noting its origins in Christian millenarianism and the hope that Christ's message would eventually lead humanity to regain the state of perfection it enjoyed before the Fall. Eighteenth-century advocates of social progress such as Joseph Priestley saw it as a process of spiritual evolution, a view developed further by liberal Christian thinkers in the following century. Idealist philosophers such as Hegel also defined history in terms of humanity's ascent of a spiritual scale, although their later followers over-simplified the message. There were speculations about the nature of the future society which would give full rein to our spiritual nature.

Although the twentieth century saw a transition to a less goal-directed model of progress, efforts were still made to defend the older vision in which humanity was the predetermined end of evolution and a particular social order the goal of social progress. Christian thinkers still tended to think of evolution as a process driven by cooperation rather than struggle, with humanity and a spiritually mature society as the goals. Even within a Darwinian framework, it has been argued that evolution is subject to constraints that leave something like humanity as the only possible end-point. From the opposite ideological position, Soviet Marxism preserved the image of a sequence of developmental stages leading to the future utopia. With the collapse of the Soviet Union there were suggestions that free-enterprise capitalism is the final end-point of social evolution.

In the eighteenth century naturalists had already begun to realize that the diversity of living forms was so great that they could not be arranged into a single linear hierarchy. The relationships were best represented as a two-dimensional map, or ─ when the time dimension was added ─ as a branching tree. Darwin used the 'tree of life' but because his theory of natural selection explained evolution in terms of adaptation to local environments his tree had no central trunk leading to humanity. Evolution was a utilitarian process in which success depended on gaining an advantage in dealing with the environment. Progress towards higher levels of organization occurred in many different ways, although only a few adaptations resulted in an overall increase in complexity. In the early twentieth century palaeontologists studying the history of life showed that progress was episodic, occurring only when a major biological innovation led to the emergence of a new class of organisms. These events were unpredictable on the basis of previous trends and could be compared to the inventions that have transformed human societies. Darwinism was a form of 'creative evolution' in which innovations were multifarious and unpredictable.

Thinkers who saw technological innovation as the way forward now had to accept that there could be no static utopia in the future: society would be in a continual state of change. There was an increased emphasis on thinking about the future rather than the past, since it was less clear that history offered a model by which future developments could be predicted. The hope of creating a planned society was replaced by the notion of the 'technological fix' that dealt with the often unanticipated by-products of innovations pioneered as beneficial. Futurology emerged as a discipline aimed at anticipating developments, although its efforts were often wide of the mark. Enthusiasts predicted a range of possible futures based on different technologies, some involving the move to a completely transhuman phase of life. Science fiction emerged as a genre providing commentary on these scenarios, often recognizing the potential disadvantages.

The chain of being depicted creation as a linear hierachy of living forms from the simplest up to the human. In the eighteenth century it was 'temporalized' to give a model for the history of life on earth implying that humanity was the last and highest product of the creative process. This image of development was boosted by a comparison with the growth of the embryo to maturity. Early theories of evolution continued to present the process as an ascent towards humanity as its goal. Parallels were drawn with the goal-directed process of embryological development, implying that the embryo recapitulates the history of life on earth. Even when naturalists realized that evolution was best represented as a branching tree rather than a ladder, the tree was given a central trunk pointing toward humanity, all other developments being mere side-branches. The claim that humanity is the goal of creation survived in various non-Darwinian theories of evolution in the late nineteenth century.

Paralleling the developments in evolutionary biology, cultural anthropologists abandoned the model in which modern Western culture was the goal of development, recognizing the diversity of cultures around the world. Archaeologists realized that different cultures had been shaped by different technological innovations. Thinkers from a range of backgrounds began to see social evolution in Darwinian terms, as a process driven by occasional innovations that were unpredictable on the basis of any general trend. H. G. Wells popularized a view of history on similar foundations, openly acknowledging the parallel with Darwinism. He and others suggested that the linkage of science and invention that had occurred in the West and led to its dominance was an example of such an unanticipated breakthrough. Counterfactual histories imagined worlds in which the key transformations had come out differently. It was now recognized that the ongoing flood of new technologies was transforming society at an accelerating rate, making it hard to predict the course of future progress.

This introduction outlines a new interpretation of the history of the idea of progress, focusing on the transition from a goal-directed model to an open-ended view in which there can be multiple forms of improvement. Developments in thinking about the history of life on earth are used as a guide to wider changes in the perception of how progress can operate. Early ideas based on the chain of being saw humanity as the goal of biological evolution, just as the first theories of social progress saw it as the ascent of a linear hierarchy of steps towards a future paradise or utopia. Darwinism transformed evolutionism by introducing the image of a branching 'tree of life' with no single goal of progress. Parallels to this transformation can be seen in twentieth-century approaches to human history and predictions of multiple possible futures based on the unpredictability of technological innovations. Progress has become less clear-cut and more open to criticism by those who reject the utilitarian basis of technological advance.