The New Penguin History of the World (189 page)

Meanwhile, after his work on quanta, Einstein had published in 1905 the work for which he was to be most widely, if uncomprehendingly, celebrated, his statement of the theory of relativity. This was essentially a demonstration that the traditional distinctions of space and time, and mass and energy, could not be consistently maintained. Instead of Newton’s three-dimensional physics, he directed men’s attention to a ‘space-time continuum’ in which the interplay of space, time and motion could be understood. This was soon to be corroborated by astronomical observation of facts for which Newtonian cosmology could not properly account, but which could find a place in Einstein’s theory. One strange and unanticipated consequence of the work on which relativity theory was based was his demonstration of the relations of mass and energy which he formulated as
E
=
mc
²
, where
E
is energy,
m
is mass and
c
is the constant speed of light. The importance and accuracy of this theoretical formulation was not to become clear until much more nuclear physics had been done. It would then be apparent that the relationships observed when mass energy was converted into heat energy in the breaking up of nuclei also corresponded to his formula.

While these advances were absorbed, attempts continued to rewrite physics, but they did not get far until a major theoretical breakthrough in 1926 finally provided a mathematical framework for Planck’s observations and, indeed, for nuclear physics. So sweeping was the achievement of Schrödinger and Heisenberg, the two mathematicians mainly responsible, that it seemed for a time as if quantum mechanics might be of virtually limitless explanatory power in the sciences. The behaviour of particles in the atom observed by Rutherford and Bohr could now be accounted for. Further development of their work led to predictions of the existence of new nuclear particles, notably the positron, which was duly identified in the 1930s. The discovery of new particles continued. Quantum mechanics seemed to have inaugurated a new age of physics.

By mid-century much more had disappeared in science than just a once-accepted set of general laws (and in any case it remained true that, for most everyday purposes, Newtonian physics was still all that was needed). In physics, from which it had spread to other sciences, the whole notion of a general law was being replaced by the concept of statistical probability as the best that could be hoped for. The idea, as well as the content, of science was changing. Furthermore, the boundaries between sciences collapsed under the onrush of new knowledge made accessible by new theories and instrumentation. Any one of the great traditional divisions of science was soon beyond the grasp of a single mind. The conflations involved in importing physical theory into neurology or mathematics into biology put further barriers in the way of attaining that synthesis of knowledge that had been the dream of the nineteenth century, just as the rate of acquisition of new knowledge (some in such quantities that it could only be handled by the newly available computers) became faster than ever. Such considerations did nothing to diminish either the prestige of the scientists or the faith that they were mankind’s best hope for the better management of its future. Doubts, when they came, arose from other sources than their inability to generate an overarching theory as intelligible to lay understanding as Newton’s had been. Meanwhile, the flow of specific advances in the sciences continued.

In a measure, the baton passed after 1945 from the physical to the biological or ‘life’ sciences. Their current success and promise have, once again, deep roots. The seventeenth-century invention of the microscope had first revealed the organization of tissue into discrete units called cells. In the nineteenth century investigators already understood that cells could divide and that they developed individually. Cell theory, widely accepted by 1900, suggested that individual cells, being alive themselves, provided a good approach to the study of life, and the application of chemistry to this became one of the main avenues of biological research. Another mainline advance in nineteenth-century biological science was provided by a new discipline, genetics, the study of the inheritance by offspring of characteristics from parents. Darwin had invoked inheritance as the means of propagation of traits favoured by natural selection. The first steps towards understanding the mechanism that made this possible were those of an Austrian monk, Gregor Mendel, in the 1850s and 1860s. From a meticulous series of breeding experiments on pea plants, Mendel concluded that there existed hereditary units controlling the expression of traits passed from parents to offspring. In 1909 a Dane gave them the name ‘genes’.

Gradually the chemistry of cells became better understood and the physical reality of genes was accepted. In 1873 the presence in the cell nucleus
of a substance that might embody the most fundamental determinant of all living matter was already established. Experiments then revealed a visible location for genes in chromosomes, and in the 1940s it was shown that genes controlled the chemical structure of protein, the most important constituent of cells. In 1944 the first step was taken towards identifying the specific effective agent in bringing about changes in certain bacteria, and therefore in controlling protein structure. In the 1950s it was at last identified as ‘DNA’, whose physical structure (the double helix) was established in 1953. The crucial importance of this substance (its full name is deoxyribonucleic acid) is that it is the carrier of the genetic information that determines the synthesis of protein molecules at the basis of life. The chemical mechanisms underlying the diversity of biological phenomena were at last accessible. Physiologically, and perhaps psychologically, this implied a transformation of man’s view of himself unprecedented since the diffusion of Darwinian ideas in the last century.

The identification and analysis of the structure of DNA was the most conspicuous single step towards a new manipulation of nature, the shaping of life forms. Already in 1947, the word ‘biotechnology’ had been coined. Once again, not only more scientific knowledge but also new definitions of fields of study and new applications followed. ‘Molecular biology’ and ‘genetic engineering’, like ‘biotechnology’, quickly became familiar terms. The genes of some organisms could, it was soon shown, be altered so as to give those organisms new and desirable characteristics. By manipulating their growth processes, yeast and other micro-organisms could be made to produce novel substances, too – enzymes, hormones or other chemicals. This was one of the first applications of the new science; the technology and data accumulated empirically and informally for thousands of years in making bread, beer, wine and cheese was at last to be overtaken. Genetic modification of bacteria could now grow new compounds. By the end of the twentieth century, three-quarters of the soya grown in the United States was the product of genetically modified seed, while agricultural producers like Canada, Argentina and Brazil were also raising huge genetically modified crops.

More dramatically, by the end of the 1980s there was underway a worldwide collaborative investigation, the Human Genome Project. Its almost unimaginably ambitious aim was the mapping of the human genetic apparatus. The position, structure and function of every human gene – of which there were said to be from 30,000 to 50,000 in every cell, each gene having up to 30,000 pairs of the four basic chemical units that form the genetic code – was to be identified. As the century closed, it was announced that the project had been completed. (Shortly afterwards, the sobering
discovery was made that human beings possessed only about twice the number of genes as the fruit fly – substantially fewer than had been expected.) The door had been opened to a great future for manipulation of nature at a new level – and what that might mean was already visible in a Scottish laboratory in the form of the first successfully ‘cloned’ sheep. Already, too, the screening for the presence of defective genes is a reality and the replacement of some of them is possible. The social and medical implications are tremendous. At a day-to-day level, what is called DNA ‘fingerprinting’ is now a matter of routine in police work in identifying individuals from blood, saliva or semen samples.

By 2005 it was becoming clear that genetic engineering would shape a substantial part of our future, in spite of the controversy created by many research programmes in this field. The ‘new’ micro-organisms created by geneticists are now patentable and therefore commercially available in many part of the world. Likewise, genetically modified crops are used to increase yields through the creation of more resistant and more productive strains, thereby giving some regions their first ever opportunity to become self-sufficient in staple foods. But while providing obvious benefits, biotechnology has also come under scrutiny for delivering food products that may not be safe and for the increasing dominance of large multinational corporations in both research and production worldwide. Such concerns have, for obvious reasons, become particularly strong when genetic research on human material has been involved, such as in work on stem cells from embryos. Many scientists fail to realize how the matters they are dealing with raise immense concerns among the public, mostly because of warnings from the history of the twentieth century.

Progress in these matters has owed much of its startling rapidity to the availability of new computer power, another instance of the acceleration of scientific advance so as both to provide faster applications of new knowledge and to challenge more quickly the world of settled assumptions and landmarks with new ideas that must be taken into account by laymen. Yet it remains as hard as ever to see what such challenges imply or may mean. For all the huge recent advances in the life sciences, it is doubtful that even their approximate importance is sensed by more than tiny minorities.

SPACE: A NEW ENVIRONMENT FOR MANKIND

For a brief period in the middle of the twentieth century the power of science was above all visible in the exploration of space. Such an extension of the human environment may well turn out one day to dwarf in significance
other historical processes (discussed at greater length in this book) but as yet shows no sign of doing so. Yet it suggests that the capacity of human culture to meet unprecedented challenges is as great as ever and it has provided what is so far the most spectacular example of human domination of nature. For most people, the space age began in October 1957 when an unmanned Soviet satellite called
Sputnik I
was launched by rocket and could soon be discerned in orbit around the earth, emitting radio signals. Its political impact was vast: it shattered the belief that Russian technology lagged significantly behind American. The full significance of the event, though, was still obscured, because superpower rivalries swamped other considerations for most observers. In fact, it ended the era when the possibility of human travel in space could still be doubted. Thus, almost incidentally, it marked a break in historical continuity as important as the European discovery of the Americas, or the Industrial Revolution.

Visions of space exploration could be found in the last years of the nineteenth century and the early years of the twentieth, when they were brought to the notice of the western public in fiction, notably, in the stories of Jules Verne and H. G. Wells. Its technology went back almost as far. A Russian scientist, K. E. Tsiolkovsky, had designed multi-staged rockets and devised many of the basic principles of space travel (and he, too, had written fiction to popularize his obsession) well before 1914. The first Soviet liquid-fuelled rocket went up (three miles) in 1933, and a two-stage rocket six years later. The Second World War prompted a major German rocket programme, which the United States had drawn on to begin its own programme in 1955. It started with more modest hardware than the Russians (who already had a commanding lead) and the first American satellite weighed only three pounds (
Sputnik I
weighed 184 pounds). A much-publicized launch attempt was made at the end of December 1957, but the rocket caught fire instead of taking off. The Americans would soon do much better than this, but within a month of
Sputnik I
the Russians had already put up
Sputnik II
, an astonishingly successful machine, weighing half a ton and carrying the first passenger in space, a black-and-white mongrel called Laika. For nearly six months
Sputnik II
orbited the earth, visible to the whole inhabited world and enraging thousands of dog-lovers, for Laika was not to return.

The Russian and American space programmes had by then somewhat diverged. The Russians, building on their pre-war experience, had put much emphasis on the power and size of their rockets, which could lift big loads, and here their strength continued to lie. The military implications were more obvious than those (equally profound but less spectacular) which flowed from American concentration on data-gathering and on
instrumentation. A competition for prestige was soon underway, but although people spoke of a ‘space race’ the contestants were running toward somewhat different goals. With one great exception (the wish to be first to put a man in space) their technical decisions were probably not much influenced by one another’s performance. The contrast was clear enough when
Vanguard
, the American satellite that failed in December 1957, was successfully launched the following March. Tiny though it was, it went much deeper into space than any predecessor and provided more valuable scientific information in proportion to its size than any other satellite. It is likely to be going around for another couple of centuries or so.

New achievements then quickly followed. At the end of 1958 the first satellite for communications purposes was successfully launched (it was American). In 1960 the Americans scored another ‘first’ – the recovery of a capsule after re-entry. The Russians followed this by orbiting and retrieving
Sputnik V
, a four-and-a-half-ton satellite, carrying two dogs, who became the first living creatures to have entered space and returned to earth safely. In the spring of the following year, on 12 April, a Russian rocket took off carrying a man, Yuri Gagarin. He landed 108 minutes later after one orbit around the earth. Humanity’s life in space had begun, four years after
Sputnik I
.