John Puddefoot is Head of Mathematics and an Honorary Chaplain at Eton College.

The subject of his book is one that is at the forefront of philosophical-scientific-theological debate. This reviewer expects the discussion to grow in significance for a long time to come - outliving the debate about the big-bang, evolution and origins. As well as theoretical questions, it raises many ethical and very practical matters. It is thus very important that theologians should be familiar with the many very profound issues involved. 

As the sub-title of the book suggests, 'Computers, Artificial Intelligence and the Human Soul', is what it is about. 

The central issue running through the book is whether or not computers will ever be conscious as the higher animals are clearly conscious and whether they will ever be self aware - able to reflect on their own existence - as clearly human beings are self aware. Each normal human being knows what it is - from within himself - to look out of himself to the outside world. For others to know me they must know something of what it feels like to me as I relate to the world beyond me. Clearly we can know computers from the outside - examining how they work - but we cannot enter into the world of a computer to feel what  a computer feels. Most of us would believe that a computer does not feel anything and never will be a conscious being. However there are those in the Artificial Intelligence community who do believe that there is nothing in principle that would stop us, one day, from making self-aware computers or robots. If one takes a strictly materialist view of reality (there is nothing but impersonal atoms and laws of physics) then self-awareness must be the product of purely physical processes in the universe. That would mean that self-awareness would be  amenable to manufacture by future generations of scientists.  On this view the mind is simply another word for brain which is a merely very complex computer.

Puddefoot shows how much of this debate is confused by the `Sliding Definition Ploy' of some writers who use words such as `intelligence', `brain', `machine', `mind' in different ways depending where they are in their discussion. 

He takes us through the many scientific, philosophical, and theological issues that surround this subject, warning us that we must not be too dismissive of capabilities of computers of the future (e.g. to provide creative solutions to human problems, and to give companionship to the lonely). However he does doubt that self-aware personhood can ever be manufactured by human beings. His theological reflections on creation and Incarnation are certainly interesting. He, for example, believes that the Incarnation was necessary for God to know human beings from the inside. He does not believe in a brain mind dualism, but believes that mind emerges from the brain but cannot be reduced to the physical processes of the brain. 

I wish John Puddefoot could have dealt more with what others have written on this subject. The very important works by Roger Penrose, Francis Crick, Keith Ward (taking very different views)  are hardly mentioned. The style is a little disconcerting. One moves through the book from passages which are very closely argued to other parts which are written with a chatty manner of expression with semi-humorous asides (not always relevant to the case being made).

Nevertheless these are small quibbles. We must be grateful to the author for helpfully highlighting many of the issues that will be debated in the years to come. He has obviously thought deeply about his subject and so many of his own reflections are profound and a real challenge to both materialists and Christians who have not yet taken the issues seriously enough.