By Henry Thomas and Dara Lee Thomas

A gay and noisy crowd was gathered in front of the Leaning Tower of Pisa. It was mostly composed of professors and students from the University of Pisa, although many townspeople were there as well. A professor of mathematics at the university was about to conduct an experiment which, as they all anticipated, was doomed to end in failure. This young man was brash enough to challenge a theory of the great Aristotle, and now he was going to turn himself into the laughing stock of Pisa.

The young professor calmly mounted the steps of the Tower. He carried a ten-pound shot in one hand and a one-pound shot in the other. In spite of the sneers of his students and the wrath of his fellow professors, he was prepared to prove the theory that two different weights, dropped simultaneously from the same height, would fall to the ground at the same time.

He released the balls. A gasp of astonishment rose from the crowd. It was unbelievable! The two balls of iron had reached the ground simultaneously.

The young professor was Galileo. And his triumph had a bitter taste.

He had proved his theory, but he had earned for himself the jealousy and hatred of his colleagues. Their minds refused to accept what their eyes had seen.

Galileo was born in Pisa, Italy, in February, 1564. As a boy, he was extraordinarily observant, and his curiosity about the world was too great to be satisfied. He could not accept as authoritative the answers which the adults about him, offered in response to his questions, and he was forever experimenting and devising tests to probe the mystery of things.

Galileo entered the University of Pisa to study medicine. But his real interests were mathematics and his experiments. When he was 19, he made his first important discovery. One day as he was sitting in church, his thoughts were interrupted by the persistent rattle of a chain. Looking about him, he discovered that the rattle came from a hanging oil lamp that was swinging back and forth. Fascinated by the rhythmic movement of the lamp, Galileo began to count its oscillations. Suddenly he jumped to his feet and rushed out of the church. A startling idea had occurred to him. It seemed to him that the movements of the lamp were regular.

Upon reaching home, Galileo put his theory to test. And so, in the swinging of an oil lamp, he discovered his important principle, the law of motion, which is applied today in the measurement of time, the eclipses of the sun and the movement of the stars.

It wasn’t long before his professors found out about his secret studies and experiments and expressed their disapproval in no uncertain terms. It was considered wrong for a student to think for himself because all scientific problems, they declared, had all been settled by Aristotle. If a student was bold enough to say anything different, his professor would settle the argument with a quotation from Aristotle: “The Master has spoken…” And that was that. But Galileo went so far as to follow up his criticism with experiments of his own. This was going too far. For the good of the university as well as the good of his own soul, they had to curb this recklessness. They notified Galileo’s father of his misdoings and the old man begged his son to settle down and obey his professors.

But the plea fell on deaf ears. Galileo had dedicated his life to the examination of nature and the pursuit of scientific truths. There could be no turning back now.

As a result of his “indiscretions,” the university refused to grant Galileo his doctor’s diploma. But his talent in mathematics was recognized by some of his professors and he was lucky enough to secure a position when the chair of mathematics became vacant, —undoubtedly because the salary was so low that nobody else wanted it!

The students hardly attempted to conceal their smiles at his lectures, and the professors hated him. How dare he try to contradict Aristotle! If he did not stop his nonsense, they would teach him a lesson he would never forget.

Galileo did not stop his “nonsense,” and the professors went into action. The “lesson” with which they threatened him was their challenge to demonstrate one of his “idiotic” theories in the presence of the entire faculty and student body of the university. Galileo accepted the challenge and conducted his historic experiment regarding the laws of bodies in motion—an experiment that, as we have seen, aroused intense antagonism among the faculty.

Despite the persecution, Galileo continued with his own studies. Finally his opponents found an excuse and had him dismissed from the university.

But the dismissal turned out to be a blessing in disguise, for with the help of influential friends, he was able to obtain a much better position at the University of Padua, where, for the first time, he breathed the air of intellectual freedom. The university was under the supervision of the Independent Venetian Republic which insisted upon the right of its scholars to pursue their scientific studies without interference from the Inquisition. No longer were his lectures greeted with sneers and catcalls. He soon became famous. Students from all over Europe came to study under him. He wrote brilliant treatises on a variety of subjects—on mechanics, motion, sound and speech, light and color, and the thermometer and, above all, the telescope.

This was the height of Galileo’s prosperity and security. He had now been in Padua for 18 years. But he was not happy. For years, he had longed for the day when he could return in triumph to Pisa, the city which had dismissed him in disgrace years before. So finally, despite the warning of his friends, Galileo returned to Pisa. This was the beginning of his tragedy.

While in Padua, Galileo had written a book concerning the movements of the heavenly bodies. For years Galileo had privately doubted the theory that the earth was fixed and everything in the heavens—the sun, moon, and stars—revolved around it. Galileo favored Copernicus’ theory which declared that the earth is a planet which revolves around a fixed sun. He did not declare this in his book, for to do so would be to deliver himself into the torture chambers of the Inquisition. But the Grand Inquisitor, Cardinal Bellarmine, had noted the fact that he had declared himself a follower of Copernicus. Therefore, on March 26, 1616, Galileo was ordered to present himself before the Inquisition.

When he arrived at the Holy Office, the Cardinal “advised” him to “abandon his wrong opinions.” Under the threat of persecution, he was not to think such thoughts, nor to defend them either orally or in writing.

Galileo was forced to obey. For a while he went quietly on with his experiments, not daring to disclose the results of his work to the world.

But in the end, Galileo was unable to suppress his ideas. He published another book on astronomy, and once more was summoned to appear before the Inquisition. But his time the charge was far more serious and death was the penalty for this “double crime.”

Galileo was ill at the time. But the Inquisitors were heartless. “Let him be seized, bound in chains and transported to Rome.”

Galileo arrived in Rome more dead than alive. His trial lasted six months. Finally he was compelled to renounce his belief. “Before the Holy Sainted gods, I swear that… I reject and detest my former heresies… I confess that my error has been one of vain ambition and pure ignorance… I now declare and swear that the earth does not move around the sun…”

But as his friends led him, trembling and exhausted, away from the Holy Office, Galileo is said to have remarked under his breath, “But the earth does move!”

When Galileo died on January 8, 1642, he left the world he loved far better informed than it was when he entered it.