By Roy Hornsby
In medieval Europe it was generally accepted that the Earth lay at the centre of a finite universe and that the sun, planets and stars orbited around it. The framework in which this astronomy was set was established by Aristotle (384 - 322 BC) in the fourth century BC while in the second century AD Ptolemy (c. 100 - 170 AD) devised a detailed yet different geocentric astronomical system (Chalmers, 1976).
During the early part of the sixteenth century, Nicolaus Copernicus (1473 - 1543) developed the first heliocentric theory of the universe (Blackburn, 1994) which he presented in 'De Revolutionibus Orbium Coelestium Libri Sex' (Six Books on the Revolution of the Celestial Orbs). The Copernican astronomy involved a moving Earth, which challenged the Aristotelian and Ptolemaic systems but by the time the Copernican view had been substantiated, the Aristotelian world-view had been replaced by the Newtonian theories of inertia, gravitation and motion (Chalmers, 1976).
The purpose of this paper is to examine how the theories of Copernicus contributed to the emergence of a scientific world-view, a view that encompassed a paradigmatic shift in world-view orientation from the medieval explanations of nature. Before the impact of the work of Copernicus can be fully appreciated however, it is necessary to have an understanding of the historical and social conditions that prevailed at that time.
The medieval schema of the universe was geocentric. That is, the Earth remained stationary at the centre of the universe while the sun, the planets and all of the stars revolved around it. However, geocentricism had been under attack. Around 1375 The Occamists, particularly in Paris had been busy with a critical philosophy and forward-looking scientific investigations. Despite retaining some of the teleological elements of Aristotelian physics, Buridan (c. 1295 - 1358) had developed a concept of inertia and of gravity as uniformly accelerated motion. Nicholas of Oresme invented the idea of analytic geometry, discovered the formula for uniformly accelerated motion and argued for the rotation of the Earth (Blake, Ducasse & Madden, 1960).
Furthermore, Nicholas of Cusa (1401 - 1464) was associated with the doctrine of the 'concordance of contraries', an attack on the Aristotelian law of non-contradiction (Blackburn, 1994) and had been willing to entertain the idea that the Earth might be in motion. In fact it has been suggested that Copernicus owed to Cusa his view that a sphere set in empty space would begin to turn without needing anything to move it (Butterfield, 1957). Despite these pockets of revolutionary thinking, medieval philosophy remained locked in pantheistic mysticism (Norris-Clark, 1994). Philosophy of the time was subordinate to Christian theology and limited by subservience to dogma. The reverence and respect displayed to authorities of philosophy and theology characterised this thought as Scholasticism. Scholastics sought not to learn new facts, but to integrate the knowledge already acquired separately by Greek reasoning and Christian revelation. Furthermore, they believed in harmony between faith and reason (Copleston, 1992). Because the scholastics believed that revelation was the direct teaching of God, it possessed for them a higher degree of truth and certitude than did natural reason. Throughout the scholastic period, philosophy was called the servant of theology, not only because the truth of philosophy was subordinated to that of theology, but also because the theologian used philosophy to understand and explain the revelation. This concern is one of the most characteristic differences between Scholasticism and modern thought since the Renaissance (Norris-Clark, 2001).
Scholastics applied the requirements for scientific demonstration as first specified in Aristotle's 'Organon' much more rigorously than previous philosophers had done. These requirements were so strict that Aristotle himself was rarely able to apply them fully beyond the realms of mathematics. It was this trend that finally led to the loss of confidence in natural human reason and philosophy that is characteristic of the early Renaissance and of the first Protestant religious reformers, such as Martin Luther (Norris-Clark, 2001).
The Christian church, still reeling from the effects of both the schism of Eastern and Western churches (1054) and of the rival Popes (1378 - 1417) found itself facing an intensified call for reform that eventually erupted in the Protestant Reformation (O'Malley, 2001). Humanism, the revival of classical learning and speculative inquiry, displaced Scholasticism in Italy during the early Renaissance of the 15th Century and quickly spread to become the principle philosophy of Western Europe. This deprived church leaders of the monopoly on learning that they had previously held (Encarta, 2001).
Martin Luther (1483 - 1546) initiated the Protestant revolution in Germany in 1517 when he published his 95 theses challenging the theory and practice of indulgences. The reform became very popular with the people and Germany became sharply divided along religious and economic lines. The reformation spread throughout Europe and led to the Peasants War (1524 - 1526). Not until 1534 when Paul III became pope did the church meet the challenge of the Protestants. Paul III, like many of his successors, did not hesitate to use both diplomatic and military measures against the Protestants. The Counter Reformation movement sought to revitalise the Roman Catholic Church. Subsequently, the Index of Forbidden Books and a new Inquisition were instituted about 1542 (O'Malley, 2001).
Astronomers also were groping for reform at the time of the birth of Copernicus. By the time that Copernicus had finished his preliminary training in astronomy, his teachers had begun to realise that although an intensive study of Ptolemy's 'Almagest' was a necessary pre-requisite to further study, to know only Ptolemy was not going to be sufficient to rejuvenate astronomy (Boas, 1962). Indeed, some astronomers held that the Ptolemaic system was so cumbersome and inaccurate that it could not be true of nature. Copernicus himself eventually wrote in the preface to 'De Revolutionibus' that the astronomical tradition he had inherited had created only a monster (Kuhn, 1962). Further to this Kuhn (1962, p. 69) stated,
"By the early sixteenth century an increasing number of Europe's best astronomers were recognising that the astronomical paradigm was failing in application to its own traditional problems. That recognition was prerequisite to Copernicus' rejection of the Ptolemaic paradigm and his search for a new one."
Copernicus however, did not seem to have a revolutionary attitude and upon rejection of the Ptolemaic system he examined again the earlier Greek astronomy. The humanist principle that all knowledge must lie with the ancients still appeared viable. Copernicus attempted nothing that others had not tried before because many astronomers had used the ancients to refute Ptolemy, however Copernicus alone chose the Pythagorean system which was to have profound revolutionary implications (Boas, 1962).
The historical evidence presented thus far suggests that Western Europe was in a state of several crises when Copernicus entered into the controversy and was ripe for a revolution of one type or another. However, Copernicus kept his work in abeyance for over thirty years and without the encouragement of George Rheticus (1514 - 1576) it is debatable whether his works would have been published at all, let alone before his death. At this point it is appropriate to note that Copernicus was a canon of the Roman Catholic Church and had been called upon by Pope Leo X to reform the calendar. The church was anxious that religious festivals be accorded their proper places in time. George Rheticus was a Protestant who was responsible for the publication of Copernicus's 'Narratio Primer' in 1540 though he handed over his position in the publication of 'De Revolutionibus' to a Lutheran pastor named Andreas Osiander (Boas, 1962). It is ironic that the Catholic Church was involved in the instigation of a reform that would eventually lead to erosion of their power over humanity. It is doubly so that it was done with the first hand assistance of two Protestants.
Traditionally, Copernicus saw his finished work only on his deathbed in 1543 and much controversy has raged over his disinclination to publish in the years between 1512 and 1539. One possible reason is that he may have been afraid of official censure. This fear was not unfounded, as publication of 'De Revolutionibus' was antecedent to much comment and criticism. Central to the Copernican system lay the point which required the most reasoned argument and one which caused Copernicus to fear ridicule from his peers; the attribution of motion to the Earth. To assume in the sixteenth century that the Earth moved required a straining of well-assured fact that could amount to the absurdity provoked by the contrary argument today. Although his book was well received by the church and used to further calendar reform little attention was given at first to its heart, the new theory. (Boas, 1962).
As mentioned previously in this paper it is inappropriate to suggest that the publication of Copernicus's great work shook any foundation of European thought immediately. A generation after his death the period of crucial transition commenced and the controversy over the correctness of the Ptolemaic or the Copernican tenet became intense. Almost one hundred and fifty years would pass before a theory of the universe that would permit explanation of the movement of the Earth and other planets was presented. This explanation, in turn, provided a framework for further scientific development. The influence of Copernicus was indeed important but it resulted not so much from his system of the skies but more from the stimulus that he gave to men who in reality were producing something very different (Butterfield, 1957).
Kuhn (1962, p. 116) discusses paradigm-induced changes in scientific perceptions during the first half century after Copernicus's new paradigm was proposed. He states:
"The very ease and rapidity with which astronomers saw new things when looking at old objects with old instruments may make us wish to say that, after Copernicus, astronomers lived in a different world. In any case, their research responded as though that were the case." (Kuhn 1962, p. 117).
In Kuhn's 'The Copernican Revolution' Copernicus is presented as a highly proficient mathematical astronomer whose very narrow mindedness outside of his chosen domain blinded him to the destructive consequences that his technical reform of astronomy entailed for the entire traditional world-view (Cohen, 1994). Kuhn's point is important, for the heliocentric theories of Copernicus replaced the geocentric view of the cosmos that further threatened the authority of the church (Norris-Clark, 1994). No longer was humanity at the centre of the universe, about which all else revolved, but rather humanity was but one small part of a much larger system in constant movement. With the importance of humanity being decentred, people began to question more than that which faith held in high regard. This resulted in original and creative thought beginning to develop outside of the revered institutions of education (Copleston, 1994), and what emerged were fresh original minds, aching to be freed from the shackles of traditional thought. The geographical discoveries, the opening up of fresh sources of wealth and the questioning of the church, heralded a new era.
In spite of this, most Renaissance scholars felt confident in tracing human history back in a continuous pedigree to Adam, the first human allowing man to retain his divinely fixed place in time and space. Finally, owing to a succession of geniuses, Copernican astronomy assimilated in the seventeenth century. This assimilation resulted in the displacement of the Earth, and man upon it. Rather than being central to the universe, the Earth and consequently mankind became insignificant elements in an infinite universe (Porter, 1990).
Grant (1971) deliberates as to why the 14th century cosmological speculations failed to bring about a Scientific Revolution in the way that Copernicus's astronomical reform was able to do. According to Cohen (1994, p. 267) Grant states,
"Saving the phenomena became the predominant attitude. The thing to do was to think up clever imaginations of how things might be rather than embark upon a relentless investigation of reality."
Grant further argues that the physical realists of the 13th century failed to produce early modern science because of their lack of confidence of the human mind to penetrate nature. Copernicus succeeded because his work made possible for the first time
"a potent union of new ideas that would challenge the traditional physics and cosmology .with the conviction, even if naive, that knowledge of physical reality was fully attainable." (Cohen, 1994, p. 267).
Apart from a few eminent mathematicians like Rheticus and intellectual radicals like Bruno, nobody was bold enough to champion the work of Copernicus. It was the genius of Johannes Kepler (1571 - 1630) who seized upon it in the late 1580's (Burtt, 1952). However, the person who contributed most significantly to the defence of the Copernican system was Galileo Galilei (1564 - 1642). He achieved this in two ways; first, he used the telescope to observe the heavens and transformed pure Copernican theory to theory substantiated through observational data. Second, he devised the beginnings of new mechanics and laid some foundations for Newtonian mechanics that would replace Aristotle's. In doing so, the mechanical arguments against Copernicus were diffused (Chalmers, 1976).
The theory that Giordano Bruno (1548 - 1600) developed from the Copernican system was that the universe forms a system of countless worlds, each of which moves around its own sun. This governs each world that leads its own proper life, emerging from a chaotic condition to a clear and definite formation and again yields to the destiny of dissolution. From the significance of the Copernican theory the 'unlimitedness' of space and time gained a clearer form and ultimately the proven hypothesis of the motion of the Earth about the Sun could furnish a rational basis for the completely new view of man's position in the universe. The anthropocentric idea which had ruled the Middle Ages became incoherent and man, as well as the Earth, ceased to be regarded as the centre of the universe and centre of the world (Windleband, 1958). Kuhn (1957, p. 264) recognises this by stating:
"The conception of a planetary Earth was the first successful break with a constitutive element of the ancient world view. Though intended solely as an astronomical reform, it had destructive consequences which could be resolved only within a new fabric of thought. Copernicus himself did not supply that fabric; his own conception of the universe was closer to Aristotle's than to Newton's. But the new problems and suggestions that derived from his innovation are the most prominent landmarks in the development of the new universe which that innovation had itself called forth."
It is not within the scope of this paper to fully examine the far reaching implications upon science and indeed mankind that have resulted from the work of Copernicus. Through the evidence presented thus far it is apparent that the mathematical reform of astronomy initiated by him was a significant intellectual event. Subsequently it set in motion a preparatory movement in astronomical and physical thought which gradually expanded until it erupted in what is now referred to as the Scientific Revolution (Cohen, 1994). His planetary theories profoundly effected man's relation to God and the universe and further, were catalytic to the transition from a medieval to a modern Western society. The Copernican theory created tremendous controversies in religion, philosophy and social theory which have set the tenor of the modern mind (Kuhn, 1957).
In conclusion, the work of Copernicus not only transformed mankind's conception of the universe but it has been markedly influential in the evolution of science and rational thought as we know it today.
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