SOME ideas are ahead of their time, and so are forgotten, to be rediscovered at a later stage when we are more receptive. The history of science is full of these blindnesses, forgettings and rediscoveries. Aristarchus of Antioeh proposed that the Earth goes around the Sun many centuries before Copernicus. Gregor Mendel's explanation of genetic inheritance lay forgotten for decades. Alfred Wegener proposed a theory of continental drift in 1912 that was only accepted in the 1970s.
This prompts the question: could people not see the evidence that was before their eyes? But hindsight can be blinding, and it is impossible to step outside our own modern view of the world and see things as our predecessors did. All we can conclude is that if they did not see the evidence, it was because they could not, because their understanding at the time constrained them to think in a particular way, to ask certain questions and interpret the answers in a particular light.
Some may be surprised that this can happen in science. After all, science has always portrayed itself as logical, almost ruthless in searching after absolute truths, an inexorable unfolding of advances in an environment of open debate.
But what human enterprise could ever be perfect in this way? Science, like any other activity, has its social, cultural and political contexts, its establishments, vested interests, sheer bloody mindedness and, above all, powerful players who can be unwilling to consider ideas that challenge their own firmly held beliefs, who are, indeed, unable to see the evidence before their very eyes.
These ways of seeing or, perhaps more accurately, not seeing, are the rich vein mined by the five essays in this thought provoking collection. All were originally lectures, a series organised for the New York public library by the New York Review - would that we could have something similar here - and now published by Granta. Each takes a different aspect within the overall theme, with valuable insights and, for me, much that was new.
First up is Jonathan Miller (medic, TV presenter and theatre director), on the history of "mesmerism" and how some people all too eagerly believed that magnetism could induce trances and fits. This led to new theories about behaviour, mind and the unconscious, that delayed our understanding of these areas (still limited, it should be said) for many years.
Stephen Gould (geologist and evolutionist), rehearses the talk he gave at the 1993 conference in TCD on "What Is Life?, arguing that the conventional images used, to depict evolution (the tree or ladder of life, with humans in the pole position) give a false picture. Better to imagine, he suggests a broad meadow of grasses with occasional tall stalks.
Daniel Kevles (who "heads the program in science, ethics and public policy" at CalTech) gives a fascinating account of how it took seventy years of courage, perseverance and luck to convince the scientific establishment that some cancers can be caused by viruses. It's a story that shows science to be a very human process.
Richard Lewontin, another evolutionary biologist, discusses the dominant mechanistic concept that views living organisms as clockwork machines, and sees their development as preordained written in the genes. In fact, he argues, things are more complex and unpredictable, and we are products of our environment as well.
But it is Oliver Sacks's contribution that really shines. Sacks a neurologist (the film Awakenings is based on his work), records his own experience of a "phantom limb", after his leg was injured in a climbing accident. It was a very real experience, he says, and apparently a common one, yet the medical profession bat the time: neither recognised nor acknowledged it. More unusually, he cites many instances where medical science identified something only to forget it, rediscovering it later, but then seeing it everywhere. Tourette's syndrome, for example, was first described in the 1880s and rediscovered in the 1970s, a kind of overnight success that took a century. Why should this be, when the disorder itself clearly didn't disappear? Perhaps, Sacks, suggests, because science in the 1880s couldn't explain its cause because it came too soon.
These are just some of the questions raised in this collection, and there are more hovering unasked beneath the surface. For example, does it matter that something is forgotten - surely the right time for an idea is when we're ready to accept it? What ideas await rediscovery even now? And is the conservatism, in built in a scientific method, that requires experiments to be repeatable before the evidence can be accepted, not a good thing? Should we chase after every new idea regardless? And if science is a product of its time and place, does this mean that European, Indian, Chinese sciences are different? That science would change if more women took part?