The claim is so often made that it has become a cliche: “Science cannot tell you what you ought to do”. The mantra that morality is a domain to which science has no access is oft-repeated by the religious, anxious to demark some sphere where religion can reign, free of irritating demands for evidence.
Such attempts to limit science’s scope are often accepted by scientists, notably Steve Gould’s tribe of NOMAds, who divide the world’s knowledge into “non-overlapping magisteria”, among which science is only “one way of knowing”. Any suggestion that science applies everywhere is derided as “scientism”. Indeed, some, such as C.S Lewis and Francis Collins, will go further, and argue that the inability of science to explain morality is an argument for God.
Yet, to many scientists, the world doesn’t seem to be divided into different spheres, with clearly demarked no-go zones where science’s methods suddenly cease to work and science comes to a shuddering halt. For example there is no clear divide between biology and chemistry, only a seamless transition that we call biochemistry.
And, if the world is seamless, then, for any question knowable to humans, science is the tool for knowing the answer (or, stating the same less provocatively, any tool that produces such an answer is a tool under the broad umbrella of science, using the same methods that work elsewhere in the seamless realm of knowledge).
So, can science answer questions about morality? Yes it can. After all, moral judgements by humans are a feature of the natural world and so are just as accessible to science as other aspects of the natural world.
The suggestion to the contrary arises principally from a fundamental confusion about what morality is, such that moral questions are often ill-posed. To explain why science can indeed answer moral questions I thus need to start with explaining morality. Continue reading