Philosophy: As St Augustine remarked, we all know what "time" is - until we try to explain what it is. The same could be said of "human freedom" especially when considered in relation to the corresponding idea of "determinism". Daniel C. Dennett's Freedom Evolves is reviewed by Patrick Masterson.
Historically, the theme of freedom vis-à-vis determinism has been considered from an "up-down" perspective - how to reconcile human freedom with the diverse "necessities" expressed by the Greek gods, or with the Christian God's divine foreknowledge of our future free actions.
In more recent times the issue has been addressed rather from a "down-up" perspective - how to give an account of human freedom compatible with the deterministic outlook suggested by the developments and discoveries of modern science. It is from this perspective that Daniel Dennett, the distinguished professor of cognitive sciences, addresses the theme of human freedom in this stimulating book. How can we make genuinely free, morally responsible decisions in a world governed by the laws of physical causation, genetic determination and environmental conditioning? Is freedom just an illusion?
The thrust of Dennett's argument is that human freedom is most certainly a reality and not at all incompatible with a deterministic world. He rejects as ineffectual any attempt to find a niche for human freedom in terms of quantum level indeterminism. However, the main object of his criticism is the Cartesian idea of freedom and moral achievement as the activity of an immaterial soul understood as a super-natural substance radically distinct from the deterministic physical world - a ghost in a bodily machine. He advocates instead a materialist conception of consciousness and freedom. This is elaborated from a basic perspective of naturalism involving the idea that the role of philosophy is to assemble the findings of the natural sciences into a unified vision of the universe including a positive account of free will which rescues it from the obscurantism of "panicky metaphysics".
Darwinian evolution is the key to this unified vision and in particular to a credible conception of human freedom and responsibility as evolving phenomena. Drawing upon a wide range of illustrative resources including game theory, computer simulation, genetics and neurology, he traces the growth of freedom on our planet from the simplest robotic forms of life through the informed "liberating" evolution of animal activity to the distinctively human achievement of freedom and responsibility by way of the evolution of culture and language.
Thus we have been enabled, by our emergence through levels of physical regularities, organic design and intentional thought and action, to participate responsibly in society. He develops an interesting discussion of how organisms can come to be designed by evolution to co-operate and eventually, at the human level to take as their own moral reasons for acting, rules of fairness which evolved naturally at a pre-moral level.
This book raises all sorts of interesting issues. Although the unscientific layman may find its, in part, rather technical discussion somewhat demanding, it is written with admirable clarity. The critique of the Cartesian "separate soul in a bodily machine" is well made and the relevance of evolutionary considerations to a discussion of freedom is skillfully presented.
It is of course controversial and its exclusive reliance on the perspective of natural science in its account of freedom and its uncompromising materialism will provoke debate. Certainly the human person is not two things: a body and an immaterial soul. But this critique does not apply, for example, to the Aristotelian conception of the soul as the form or actual organization of the human body and of which thinking and free decision are vital activities not performed by any bodily organ.
Dennett's claim, viable perhaps from the perspective of natural science, that "consciousness is 'identical' to physical brain states" is prima facie counterintuitive - at least as regards higher cognitive and volitional acts. It raises the question whether the impersonal objective perspective of natural science is able to give a total portrayal of such activity. Or should it be complemented by discourse more appropriate to the irreducibly first-person perspective of human subjectivity?
As Thomas Nagel reminds us, there is much about the world and ourselves that cannot be adequately understood from an exclusively objective standpoint and the attempt to do so leads to the denial of patently real phenomena. The irreducibly subjective character of conscious mental processes, whatever may be their intimate relation to the operation of the brain, is a fundamental feature of reality without which we couldn't do science or anything else.
These remarks only emphasize the provocative and stimulating character of this important book, which, remarkably, throws new light on a well-worn topic.
Patrick Masterson is an emeritus professor of University College Dublin and former president of the European University Institute, Florence
Freedom Evolves. By Daniel C. Dennett. Allen Lane, Penguin, 347pp. £20