The "scientific worldview" is immensely influential because the sciences have been so successful. Their achievements touch all our lives through technologies and through modern medicine. Our intellectual world has been transformed through an immense expansion of our knowledge, down into the most microscopic particles of matter and out into the vastness of space, with hundreds of billions of galaxies in an ever-expanding universe.

But now that science and technology seem to be at the peak of the power, when their influence has spread all over the world and when their triumph seems indisputable, unexpected problems are disrupting the sciences from within. Most scientists take it for granted that these problems will eventually be solved by more research along established lines, but some, including myself, think that they are symptoms of a deeper malaise.

In my new book The Science Delusion, published today, I argue that science is being held back by centuries-old assumptions that have hardened into dogmas. The sciences would be better off without them: freer, more interesting, and more fun. The biggest scientific delusion of all is that science already knows the answers. The details still need working out, but the fundamental questions are settled, in principle.

Contemporary science is based on the philosophy of materialism, which claims that all reality is material or physical. There is no reality but material reality. Consciousness is a by-product of the physical activity of the brain. Matter is unconscious. Evolution is purposeless. God exists only as an idea in human minds, and hence in human heads.

These beliefs are powerful not because most scientists think about them critically, but because they don't. The facts of science are real enough, and so are the techniques that scientists use, and so are the technologies based on them. But the belief system that governs conventional scientific thinking is an act of faith.

The credibility crunch for the "scientific worldview"

For more than 200 years, materialists have promised that science will eventually explain everything in terms of physics and chemistry. Believers are sustained by the faith that scientific discoveries will justify their beliefs. The philosopher of science Karl Popper called this stance "promissory materialism" because it depends on issuing promissory notes for discoveries not yet made. Despite all the achievements of science and technology, materialism is now facing a credibility crunch that was unimaginable in the twentieth century.

In 1963, when I was studying biochemistry at Cambridge University, I was invited to a series of private meetings with Francis Crick and Sydney Brenner in Brenner's rooms in King's College, along with a few of my classmates. Crick and Brenner had recently helped to "crack" the genetic code. Both were ardent materialists and Crick was also a militant atheist. They explained there were two major unsolved problems in biology: development and consciousness. They had not been solved because the people who worked on them were not molecular biologists--nor very bright. Crick and Brenner were going to find the answers within 10 years, or maybe 20. Brenner would take developmental biology, and Crick consciousness. They invited us to join them.

Both tried their best. Brenner was awarded the Nobel Prize in 2002 for his work on the development of a tiny worm, Caenorhabdytis elegans. Crick corrected the manuscript of his final paper on the brain the day before he died in 2004. At his funeral, his son Michael said that what made him tick was not the desire to be famous, wealthy or popular, but "to knock the final nail into the coffin of vitalism." (Vitalism is the theory that living organisms are truly alive, and not explicable in terms of physics and chemistry alone.)

Crick and Brenner failed. The problems of development and consciousness remain unsolved. Many details have been discovered, dozens of genomes have been sequenced, and brain scans are ever more precise. But there is still no proof that life and minds can be explained by physics and chemistry alone (Chapters 2, 5 and 9).

Materialism provided a seemingly simple, straightforward worldview in the late nineteenth century, but 21st century science has left it far behind. Its promises have not been fulfilled, and its promissory notes have been devalued by hyperinflation.

In The Science Delusion, in the spirit of radical scepticism, I turn each of the ten dogmas of materialism into a question. Entirely new vistas open up when a widely accepted assumption is taken as the beginning of an enquiry, rather than as an unquestionable truth. For example, the assumption that nature is machine-like or mechanical becomes a question: "Is nature mechanical?" The assumption that matter is unconscious becomes "Is matter unconscious?"

The sciences are being held back by assumptions that have hardened into dogmas, maintained by powerful taboos. I believe that the sciences will be regenerated when they are set free.