Mark Bold

‘The revolutions of thought which shape the basic outlook of an age are not disseminated through text-books – they spread like epidemics, through contamination by invisible agents and innocent germ-carriers, by the most varied form of contact, or simply by breathing the common air.’ (1979, p151)

Koestler is describing the impact of the Copernican revolution in the sixteenth century, comparing it to changes in belief that spread through Western society from the work of other writers, such as Darwin and Marx. The terminology is eerily memetic, yet his real concern is to show how established ideas (in this case the Ptolemaic belief that the sun revolves around the earth) hold sway over thinkers until there is a sudden break with the past, and a completely new belief system becomes accepted. The process of scientific advance he describes is very similar to the paradigm shift, introduced by Thomas Kuhn in The Structure of Scientific Revolutions (published within a few years of The Sleepwalkers), and now a familiar term. Both writers are trying to show that science does not move forward in a gradual advance of knowledge, but in fact jumps forward and sometimes sideways in leaps and gear shifts.

The Sleepwalkers takes a sweeping view of the history of cosmology from the Babylonians and Egyptians thousands of years ago, through to Newton in seventeenth century England. It concentrates on the characters involved in the discoveries, especially Copernicus, Kepler and Galileo. Having described the speculations about the planetary system of early civilisations, and the absence of any real development of these ideas through the Dark Ages, Koestler then enjoys bringing alive the discoveries of his protagonists as the narrative moves up to and into the Renaissance. For a subject that might seem quite intimidating in its ambition, it is very readable because of the biographical approach.

Koestler uses the metaphor of sleepwalking to describe on an individual level the process of scientific discovery. Each of the main characters, as he describes them, seems to happen upon important discoveries while searching out something else. This applies especially to Kepler, whose Chaplinesque manner is vividly contrasted with his genius. Kepler spent his life erroneously believing that the solar system ought to be explainable in terms of the five Pythagorean solids, an idée fixe, as Koestler terms it, that somehow led him to discover his laws of celestial motion, laying the foundations for Newton and modern astronomy. Koestler is a little less affectionate towards his other characters, in particular Galileo, whose arrogance and recalcitrance he blames for the needless interference of the Inquisition in the elucidation of the heliocentric system.

A subtle theme that emerges from Koestler’s humanistic descriptions and recreation of the atmosphere of the Renaissance is that of creativity and the uomo universale. Koestler, when he speculates about the nature of the creative process (as he did more fully in his 1964 The Act of Creation) puts emphasis on the wide range of influences on the minds that were so fertile in this period, and a lack of the specialisation that is a core feature of all scientific, if not all academic disciplines today. The ‘common air’ that inspired the genius of Leonardo and Michelangelo as well as the discoveries of Kepler and Galileo was the free exchange of ideas and argument amongst men not cornered in a specialisation. Their minds were open to the developments surrounding them as the unhealthy dogma of the ancients, especially Aristotle, loosened, and arts and sciences went through what Koestler terms a ‘watershed’.

In fact, Koestler goes further, and laments the split that occurred between religion and science at this time. He blames Galileo as one of the principle causes of the schism, in his role of angering the Church over Copernican theory. Contrary to myth, Galileo was never tortured by the Inquisition, nor spent any time in prison (he was under house arrest in villas in Tuscany and the Vatican) for keeping to his beliefs, and indeed, the myths about Galileo sprang up, Koestler adds, as each side in the dispute began to spread its own propaganda. Before the split, speculation about the heavens had been linked with an awe about the workings of the mind of God, about how He had constructed such an elegant system. Even before Christianity, there had been a animist belief and respect for the universe. When the ‘mystic and savant’ split apart, man became all the poorer, halved, as Koestler sees the rational and religious sides of human nature as complimentary. Both draw on the intuitive and also the logical capabilities of man; both are required to fully access Man’s creative potential and live fully.

KOESTLER, Arthur (1979) The Sleepwalkers London: Penguin