His 2006 book "The Music of Life" examines some of the basic aspects of systems biology, and is critical of the ideas of genetic determinism and genetic reductionism. He points out that there are many examples of feedback loops and "downward causation" in biology, and that it is not reasonable to privilege one level of understanding over all others. He also explains that genes in fact work in groups and systems, so that the genome is more like a set of organ pipes than a "blueprint for life". His 2016 book "Dance to the Tune of Life" sets these ideas out in a broad sweep from the general principle of relativity applied to biology, through to the role of purpose in evolution and to the relativity of epistemology.