Most of the Critics section in this week's issue of the New Statesman , out today, is devoted to a philosophy special. The philosopher and writer Raymond Tallis  reviews two of the latest contributions to the burgeoning science of consciousness, Antonio Domasio's Self Comes to Mind and Nicholas Humphrey's Soul Dust. Humphrey  recently spoke to the New Statesman about his new book.
Can you explain the title of your new book, Soul Dust?
I'm arguing that consciousness is like a kind of fairy dust which turns everything it touches into gold. "Dust" means matter too, but what I also want to do is reintroduce the soul as a respectable issue for evolutionary psychology and philosophy.Soulfulness or spirituality is a major achievement of natural selection. It allows us to live in this extraordinary ecological net which I call "soul land".
What's distinctive about your approach?
Philosophers and scientists have assumed that consciousness must be giving us some new skill or faculty of cognition. Then they get verypuzzled, because it doesn't seem to. I argue that consciousness changes our psychology in terms of our attitude toward the world we live in, rather than giving us a new skill.
Why do you want to make the idea of the soul respectable again?
My position as a natural historian of consciousness is to take seriously the way consciousness affects people's outlook on life. They may, for example, have the Christian idea of the soul, with all the baggage that comes with it.But spirituality and the belief in the soul actually came before religion, and religion has been parasitic on them. I don't agree with the view, now rather common view among evolutionary psychologists, that religion was evolutionarily adaptive.
How do you account for the emergence of religion then?
It emerged for cultural reasons. It's an extraordinarily powerful "meme", if I can use that word. But memes don't have to serve the interests of the hosts who carry them. I'm not arguing that religion is a bad thing in terms of the consequences it has. My point is that people had a spiritual side before religion took advantage of it.
You describe consciousness as a "magical mystery show" that human beings lay on for themselves. Why do we do that?
Sensation didn't have to have the qualities it does. They seem to have been elaborated by some really clever things going on in the brain. The question is why we have evolved them? My answer is that they change our relationship to the world and make it seem a more mysterious and magical place, and make us, as the enchanters of the world, see to be extraordinary, almost supernatural beings.
Indeed, you point out that we are tempted to treat consciousness as something "out of this world".
It seems to be something that is beyond explanation in terms of what we know about the material world. That's a claim which many people, religious believers and philosophers, always make.
So do you see your job in this book as breaking the spell that consciousness puts on us?
I don't think I'm breaking it. I'm drawing attention to it, and marvelling at it. Of course, I'm also trying to give a material explanation for what looks like magic. But the emphasis is on the fact that it does look like magic, and the questions I go on to ask are about what purpose it's serving.
What about animals which are conscious but don't, as far as we can tell, feel so special?
There may be varieties of consciousness which have at least some of the psychological effects I described and which we could recognise in dogs or chimpanzees, say. We should be able to see signs of it in the playfulness and the exuberance of an animal, in the way it delights in being itself.
Your background is in experimental psychology rather than philosophy. What do your more empirically minded colleagues think of what you're doing?
I'm waiting to see. The challenge will be to "prove it". If I am doing this in the name of science, then I ought to come up with predictions. But that is a tough order. I just hope that the ideas are taken seriously and that people who are much cleverer than me will realise that this could haveinteresting and testable consequences.
Interview by Jonathan Derbyshire
Nicholas Humphrey's "Soul Dust: The Magic of Consciousness" is published by Quercus (£18.99)