The Plurality of Worlds, Part 1: From Antiquity to the Eighteenth Century

John Harney
Magonia 4, Summer 1988.
We may perhaps gain some insight into the real nature of the controversy concerning the extraterrestrial hypothesis (ETH) as an explanation for UFO reports by examining the historical development of the idea of life on other worlds. Our attitudes to this question are determined, to some extent, by the traditional world pictures and world views which we have inherited.
Traditional western thought is derived from a fusion of Graeco-Roman and Hebrew ideas, together with the development of Christian theology. Western philosophy and theology were increasingly influenced, from about the time of the Reformation, by the rise of modern science.
The ancient Greeks entertained various ideas concerning the nature of the universe but the model which dominated medieval thought was that of Aristotle. For him the Earth was stationary at the centre of the Universe. The sublunar world of gross matter consisted of the four elements, earth, water, air and fire and natural movement in this sphere was upwards towards the lunar sphere, downwards towards the centre of the Earth. The rest of the universe was quite different in nature, consisting of a perfect, unchanging substance called the ether, or quintessence. The natural movement attributed to this substance was circular. Thus all of the unchanging heavenly bodies moved eternally, with uniform motion in circular orbits around the Earth. Although changes obviously took place on Earth the Forms (ideas) were eternal, so that although individuals were born and died, humanity and the environment remained basically the same.
In such a system there could be no room for ‘other worlds’ as we generally understand the term. Perhaps equally importantly, there was no idea of progress, of change through time, which would enable us to devise the means to visit other worlds, or for beings from other worlds to get around to visiting us.
The early Fathers of the Church drew upon these ideas for their formulations of Christian thought. Thus Christian theology became almost inextricably entwined with Aristotelian physics. Christianity is a historical religion which views the world as having had a beginning (Gen. 1:1) and being destined to come to an end, when all things will be made new (Rev 21:5). This is incompatible with the eternal and basically unchanging world of the Greeks, so why did Christianity not simply follow traditional Jewish thinking?
The answer lies with the beginnings of the rise of Christianity. St Paul preached to Gentiles as well as to Jews and his insistence that Gentile converts need not be circumcised or practise the various ritual observances of Jewish law obviously facilitated the rapid growth of the new religion. Paul was well aware of the problems caused by bringing together people of different traditions to share a common faith, as their ways of thinking were so different. He observed that ‘… the Jews require a sign, and the Greeks seek after wisdom.’ (1 Cor. 1:22.) In the beginning the church at Jerusalem was the predominant one, but the centre of gravity of the Church shifted to Rome after the destruction of Jerusalem in AD 70. This event removed Christianity from its Jewish context and led to its gradually becoming an integral part of the Roman-Hellensitic world.
As well as suffering persecution from the Roman authorities the early Church had other problems, in particular the threat to its unity and integrity posed by Gnosticism. The Gnostics believed that matter was inherently evil, and this belief although consistently condemned by the Church, has had a strong effect on Christian thought throughout the centuries and right up to the present day.
The uneasy compromise in Christian thought between the Jewish and Greek traditions was institutionalised by the Council of Trent (1546), which decreed that Biblical interpretation should not depart from the general consensus of the Church Fathers. The Council of Trent had been convened in order to reform the Church and in doing so it gave more rigorous definitions to certain doctrines which were a source of confusion because of doubts as to their proper interpretation or importance. The definitions arrived at by the Council served to highlight the differences between the Church of home and the growing Protestant sects.
This increasing disunity in Christendom gave an impetus to an alternative approach, or third force, which was a campaign to develop a new religion which would reconcile Protestant and Catholic by being universally acceptable. This religion was to be based on the study and interpretation of a collection of occult writings attributed to one Hermes Trismegistus, but actually written by a number of unknown authors. One of the Hermetic beliefs was that there was life on other worlds. This idea arose naturally from the pantheistic nature of Hermetism. The universe itself was alive and individuals were regarded as being transitory manifestations of the eternal life of the self-sufficient universe. The sun was placed at the centre of the centre of the universe because it was the obvious source and sustainer of life on Earth.
An enthusiastic purveyor of such ideas was Giordano Bruno, who was burned at the stake in 1600 for his pantheistic heresies. Galileo came under suspicion for a time, when it was thought that his reasons for wishing to place the sun at the centre of the universe might be Hermetic – and therefore heretical – rather than purely scientific.
Up to the time of Galileo Galilei (1564-1642) there had not been very much scope for speculation about life on other planets, because of the general acceptance, by the scholastic philosophers, of the cosmology of Aristotle, which I have described above; although there was speculation as to whether there might be a large, or infinite, number of Aristotelian universes. The picture changed when Galileo argued in favour of the system devised by Copernicus, supporting his arguments with accounts of his telescopic observations.
As the gradual acceptance of the new cosmology changed the received world picture it also changed the world view. The idea emerged of the Earth as one of several planets orbiting the sun, which was but one of millions of stars. Thus the Earth was now seen as not being unique: other planets were basically similar. This gave rise to speculation based on analogical arguments (eg. ‘The Earth is a planet and is inhabited: Mars is a planet, so Mars may be inhabited’).
This kind of argument has continued to the present day, but for a long time it was complicated by theological considerations. Many thinkers were concerned that Scripture had nothing to say about other worlds, although a nineteenth-century Scottish schoolmaster, Thomas Dick, claimed in his Sidereal Heavens (1840) that the doctrine of the plurality of worlds was embodied in many passages of Scripture (eg. Heb. 1:2, 11:3).
The belief that there are rational beings on other planets was important to Christian thinkers of the seventeenth and eighteenth centuries because of their need to try and gain some insight into God’s purpose in creating the universe. There was no problem with the small, Aristotelian universe, enclosed by the sphere of the fixed stars; it had been created for the benefit of humanity. The mathematician, philosopher and physicist, Christiaan Huygens (1620-95) argued that as most of the universe could never even be seen by man, he could not believe that a wise Creator would put all His creatures on one spot, and leave the rest of His immense universe devoid of life. He also made the moral point that speculation that God had created rational beings on thousands of ether worlds would reduce the tendency for humanity to have an exaggerated idea of its own importance in Creation. This point was also made by Pierre Gassendi (1592-1655), who also pointed out that as God Is infinite and incomprehensible, His creation also must be infinite and thus far greater than anything that could be known to man.

Descartes separated the physical from the spiritual so that the physical universe could be thought about and investigated without
recourse to metaphysical ideas, and sought
to explain all natural events as the effects
of matter in motion

Thus we can see that the philosophers who discussed the plurality of worlds in the wake of the Copernican revolution were arguing by analogy and, perhaps more importantly, employing the idea of final causes. However, this way of thinking, which combined the natural and the supernatural in attempts to solve philosophical and scientific problems, cams under increasing opposition with the development of a mechanistic philosophy.The principal developer of a mechanistic philosophy was René Descartes (1591-1650). He separated the physical from the spiritual so that the physical universe could be thought about and investigated without recourse to metaphysical ideas. He sought to explain all natural events as the effects of matter in motion. As one particle moved it displaced other particles, but without leaving any gaps, rather like goldfish swimming around in a bowl. In devising this scheme Descartes intended to found a scientific method based on certainty, so that the universe could be described in terms of simple cause and effect, like the workings of a clock. However, his ideas were attacked on both religions and scientific grounds.
A religious objection was that in describing a deterministic universe, he was leaving no room for the working of divine providence, so his ideas would lead eventually to atheism. Also, for Descartes, belief in God was attained by the exercise of will rather than intellect. This was unacceptable to many other philosophers, for in the seventeenth century natural theology was becoming increasingly important and many books were published which used the argument from design in an attempt to persuade doubters of the existence of God, and of His wisdom and goodness. This emphasis on natural theology arose largely because of a general weakening of religious faith, particularly among intellectuals, which could be attribute, to the constant quarrelling among the numerous sects into which Christianity hart become divided.
The chemist Robert Boyle (1617-92), one of the founder members of the Royal Society, said that by neglecting final causes, Descartes was throwing away one of the strongest arguments for the existence of God and one of the most impressive proofs of His wisdom. He did not agree that God’s purposes were inscrutable unless conveyed to mankind by revelation, but that at least some of them could be discovered by the observation of nature.
It was this empirical approach that Boyle shared with other natural philosophers of his day, such as Hook, Newton and Pascal, which clashed with the rationalism of Descartes. Because light goes through empty space, Pascal argued, that was no excuse for philosophers to fill it with an imaginary substance just to make the process comprehensible. Descartes’ clear ideas and logical deductions from them did not necessarily correspond with reality. It was the task of the natural philosophers to discover what the laws of nature actually were, and not what they should be according to our ideas of what is or what is not rational.
This approach was both a scientific and a theological criticism of Cartesian philosophy. His contemporaries accused Descartes of relying too much on his own unaided reason and were able to show that some of his scientific theories were wrong, notably his rules for the behaviour of colliding bodies. Isaac Newton (1642-1727) attacked his ‘vortex’ theory of celestial motion. He also said that vortex motion would quickly decay and illustrated his arguments by studying the behaviour of various fluids when stirred.
Newton’s criticism also had theological motives. He did not like the identification of matter with space, as he could conceive of empty space as having always existed as a great void in which God decided to create matter. Whether or not the concept of space existing all by itself has any meaning is an interesting philosophical problem, butNewton’s ideas of the universe as particles of matter with nothing but empty space in between them gave rise to certain difficulties. Descartes had explained how bodies could act on one another at a distance, and rejection of his idea of the universe being completely filled with matter made interactions such as gravity and magnetism profoundly mysterious. Newton was thus unable to explain gravity without attributing it to the agency of God. However, Newton and some of his contemporaries did not want to devise models of the universe in which everything could be explained in terms of simple, mechanical cause-and-effect relationships. Such models would be too deterministic, leaving no scope for free will or divine providence, this being one of the main objections to Descartes’ system of interlinking vortexes.
When Descartes denied that animals have souls he thought that he was doing a service to religion by emphasising man as a special creation, different in kind from the animals, not superior simply by possessing a more elaborate brain. His critics did not see it that way, though, and saw Descartes’ analogies of animals with soulless automata as a possible first step towards atheism, by gradually devising explanations of all animal, and even human, behaviour in purely mechanical terms. Of course, his critics were right in the long term, but in the seventeenth century the idea was used to support rather than erode religious belief.
I have dealt with these seventeenth century controversies concerning science and theology to show that these two subjects did not develop independently. This meant that an attack on theology could also undermine the philosophical bases of scientific theories. Most readers will have some idea of the ferment of ideas which characterised the eighteenth century and will realise that eighteenth-century thought can not be summarised briefly. However, two important points are the movement to exclude God from natural philosophy (i.e. science) and attacks on the idea that science can provide us with knowledge of the universe which is certain, rather than merely probable.
Hume also attacked the concept of
cause and effect and insisted that
knowledge of the world must be
based on experience and not
on the a priori assumption of a
rational order imposed on nature.

One of the most notable of eighteenth century philosophers (at least from the British point of view) was David Hume (1711-76). He used various arguments in his attacks on natural theology, one of them being that the theologians argued from the a priori assumption that the God whose existence they were seeking to establish through the observation of nature possessed all the attributes of the God of Christianity. He also attacked the concept of cause and effect and insisted that knowledge of the world must be based on experience and not on the a priori assumption of a rational order imposed on nature. Of course, the scepticism of Hume and others did not destroy religious belief; it merely added to the plethora of competing creeds and philosophies. It also served to build up an intellectual climate in which nothing would for long be taken for granted or remain unquestioned.
In the seventeenth century there had been a number of books published which were devoted to speculation about the possible inhabitants of other worlds, for example The Discovery of a New World, by John Wilkins (1638) and Cosmotheoros by Christiaan Huygens (1698). Both of these authors had theological motives. For them the principle of sufficient reason required the universe to be teeming with life.
Their speculations, and those of other authors of the period, were imaginative, but there was something lacking. This was the idea of development and fundamental changes either of humanity or of the universe. This meant, of course, that their ideas about life on other worlds tended to be rather anthropomorphic, although Wilkins, Huygens, and other writers on the same subject were careful not to describe the hypothetical inhabitants of other worlds as human.
Another notable book on the same theme was Entretiens sur la Pluralité des Mondes by Bernard le Bovier de Fontenelle, published in 1686. However, Fontenelle’s aims were somewhat different from those of the writers mentioned above. He was one of the philosophes, whose writings culminated in the Enlightenment (or Age of Reason) and the French Revolution of 1789. The philosophes were deists or atheists; who regarded religion as superstition. They believed that the pursuit of reason would lead to happiness. Many of those who lived on until 1789 were sadly disillusioned as they fell victims to the Revolution.In contrast to the optimism of the philosophes, many seventeenth and eighteenth century thinkers saw human history as a story of degeneration rather than progress. A notable example of this attitude was Gibbon’s Decline and Fall of the Roman Empire (1776-88), which saw history since the Roman Empire as a story of the continuous decline of civilisation.
Our present ideas about life on other planets are influenced by ideas which have developed since the eighteenth century. However, I have attempted to outline the ideas entertained by intellectuals, ignoring, popular beliefs and folklore. In spite of the ideas which have developed from the late eighteenth century to the present day, such as evolution, Marxism, relativity and quantum theory, the world views of many modern UFO enthusiasts seem to me to be derived from the distant past, rather than from the science and philosophy of the twentieth century. We have, for instance, the benevolent ‘apace brothers’ of so many of the contactee stories of the fifties, who come to warn us of the error of our ways, and who seem real, yet exist on a higher plane, being made of matter which has ‘higher vibrations’ than earthly matter. This reminds us of the Aristotelian universe in which all supralunar beings are made of ether, which is incorruptible. This concept of the earth being made of ‘gross’ matter unlike the rest of the universe, is obviously connected with Gnostic beliefs which regard matter as being inherently evil.
The ‘nuts and bolts’ ufologists appear to be passionately eager to find evidence of the reality of intelligent life elsewhere in the universe. Although they rarely display overt theological motives, their concern perhaps has a similar motive to that of the philosophers of the seventeenth century, in that they believe there must be some reason for the existence of such an immense universe.In this article I have tried to sketch the intellectual background which most of us quite unconsciously draw upon when we consider the possibility of life on other planets. I hope in future articles to review some of the more important scientific and philosophical ideas as they have developed from the eighteenth century to the present day, discussing how they might effect our attitudes to UFO reports and speculations about extraterrestrial life.