Journal of European Baptist Studies, Volume 9, Number 2, January 2009

logy can be added to the list, as it studies the behaviour of the whole organism in its environment. One of the most influential ideas carried forward from the work of the logical positivists in the 1920s was a plan for the unification of the sciences by showing that the human sciences could be added to the hierarchy, and then arguing that the laws of each science could be reduced to (i.e., be shown to be special cases of) the laws of the next lower discipline. In other words, the higher could be reduced to the lower in the sense that the behaviour of the higher-level entity could be explained in terms of the behaviour of its parts. The ultimate consequence would be that the behaviour of all of the entities in the universe could be shown to be a consequence of the laws of physics. There are indeed many questions that arise at, say, the chemical level that can only be answered by means of knowledge of atomic physics, the level below. The success in explaining chemical reactions in terms of atomic physics was largely responsible for promoting this reductionist approach to science. 4 Francis Crick, The Astonishing Hypothesis: The Scientific Search for the Soul (New York: Charles Scribner’s Sons, 1994), p. 3. Journal of European Baptist Studies However, we are now recognising that reducing a system to its parts usually only provides partial understanding. This should be common sense when we think about the human level. Much of who we are and what we do is affected by our biology - by our neural systems and genetics. However, (and here I quote sociologist Sal Restivo): ‘We do great harm to ourselves and our planet if we rely on [natural scientists] for our self-image as persons and as a species. We are, indeed, thermodynamic systems and we run at some level according to the laws of physics, biology, and chemistry. But what we are above all is a social and cultural thing, a society, a social being. . . . We are, individually and collectively, social facts’ (personal communication). It is now increasingly the case that this phenomenon, referred to as top-down causation, applies equally among the natural sciences themselves. That is, we often need to move to a third level or higher to answer questions at level 2. Evolutionary biology is rife with examples of both bottom-up and top-down explanation. Mutations are explained primarily via physics and chemistry, while survival of an altered life form is largely explained environmentally; that is, in terms of factors germane to the science of ecology. So the defeat of reductionism in general, and in particular the defeat of reductionism in our understanding of human beings, requires the development of the concept of downward causation. We need to show that we are not mere aggregates of our biological parts, but that we, as complex systems, in relation to our environment, are causal players in our own right, and that we have downward control over our own