Galileo (1918)/Chapter 12
Viviani was Galileo's first biographer, but as he only knew him for the last few months of his life, many of his statements, being derived from hearsay, are not trustworthy. He gives a description of his appearance as he knew him, a square, well-knit figure rather above medium height, and a cheerful and pleasant face with plenty of hair and beard which had been of a reddish colour. His temper was short, but he was ailing for nearly fifty years, and much is forgiven in such a case, even without the provocation he was continually encountering for a longer period still. He was fond of congenial society, but rarely discussed mathematical or mechanical subjects with strangers. He was also fond of gardening, and country life generally. He was rather particular about wine, of which perhaps his liking was too great, considering the infirmities of body and of temper from which he suffered. He had a remarkable memory for classics and poetry, old songs and stories. He was a magnificent teacher, being able to grasp the difficulties of less rapid thinkers in a way not always found among professors.
When we come to consider his claims to fame, it is necessary to pay due regard to a sense of proportion. It is a commonplace to observe that his astronomical discoveries were bound to be made as, a direct consequence of the invention of the telescope, so that, though he is popularly known almost entirely by them, they cannot be rated very highly in comparison with his achievements in other directions. The science of dynamics may be said to have been started by him, and he came very near to more than one great discovery for which later scientists have, earned undying glory. In his meditations on Gilbert's treatise on the magnet, for instance, the theory of gravitation does not seem far away. There is no doubt that in statics, dynamics, and hydrostatics, his work was of much more value to succeeding generations than the astronomy that brought him into such trouble.
As regards the great controversy about the Copernican system, several suggestions have been made which we find a difficulty in accepting. It has been argued that Galileo's violent support of his case, like that of a "flat-earth" enthusiast, was due to the insecurity of his convictions, the inference being that he was not satisfied himself. But surely reformers are bound to make far more noise in proportion to their numbers than those who are contented with things as they are. On the other hand, it has been argued that, being absolutely sure he was right, he ought therefore to have defied the Inquisition, daring them to punish him. Would anybody, one may be permitted to inquire, really be prepared to go to the stake in defence of the "dogma" that twice two are four? Such martyrdoms have nearly always been associated with religious persecution, and not with any scientific controversy, however acrimonious: and the ostensible ground of Galileo's trial was theological, as otherwise it would have been difficult, if not impossible, for his enemies to attack him with such disastrous effect. In just the same way had his dialectic forerunner Socrates been condemned ostensibly for "impiety," and paid the penalty with his life.
The path of one born before his time is indeed liable to be a thorny one, but those who follow reap the benefit, finding many of the thorns trampled away by the pioneer, and the road made plain, though often difficult to follow or to widen. To that extent Galileo's sufferings must have hastened the triumph of Copernicanism. This triumph was inevitable in any case, just as practically all the things for which the Chartists rose in riot, have since been peacefully enacted.
The enduring fame of Galileo, who now ranks among the greatest of Italians and of philosophers, is emphasised not only by monuments and inscriptions but by a national edition of his works in twenty volumes, and by the celebration of such epochs as the tercentenary of his birth, held at Pisa in 1864, and that of his inaugural lecture at Padua, which representative scientists of the world attended at Padua in 1892.
We will conclude with an extract from Professor Grant's appreciation of Galileo's services to the science of motion. He says: "The sagacity and skill which Galileo displays in resolving the phenomena of motion into their constituent elements, and hence deriving the original principles involved in them, will ever assure to him a distinguished place among those who have extended the domains of science. It is perhaps impossible, in the present advanced state of mechanical philosophy, to form a just estimate of the difficulties which then interposed towards a precise and luminous view of the fundamental principles of motion. It is universally admitted that those phenomena which come under the daily observation of mankind, and which on that account do not possess any salient features on which the imagination can repose, are generally those which are most liable to elude the inquiries of ordinary minds. The principles which Galileo established by his sagacious researches had the effect of elevating mechanical science to the dignity of one of the most important subjects which can concern the attention of mankind. They were essential elements in the train of investigation which conducted Newton to the sublime discovery of universal gravitation; and in fact they constitute the basis upon which the vast super-structure of the physico-mathematical sciences has been reared."
aberdeen: the university press