The philosopher, astronomer, mathematician and priest Giordano Bruno was executed for heresy on February 17, 1600, by order of Pope Clement VIII. He found his end on a pyre on the Campo de’ Fiori in Rome, where a statue of him stands today. Bruno is widely regarded as one of the most adventurous thinkers of the Renaissance.
In 1565 Bruno joined a Dominican monastery in Naples where he took the name ‘Giordano’. Because of his liberal attitude, he was soon suspected of having heretical ideas. Nevertheless, Bruno was ordained a priest in 1572. After that, however, he continued to chart his own course. For example, to the dismay of other clerics, he spoke freely about Arianism, a doctrine condemned by the Church that, among other things, denied the divinity of Christ. Liberal views on the Trinity were also sensitive. Because of his statements, there were plans to start a heresy trial against the liberal priest. Bruno decided to pack his bags and left the Dominican Order. In Naples, shortly afterwards, the authorities found banned comments from the humanist DesidirusErasmus with Bruno. To avoid persecution, he then fled again. Bruna put down his priestly robes and for a while joined the Calvinists in Geneva, but there too he eventually ran into problems because of his liberal ideas.
An infinite universe
What were Giordano Bruno’s “heretical ideas” anyway? In any case, it was important that the Italian adhered to the so-called heliocentric theory of Copernicus. According to this teaching, the sun was the center of the universe and not the earth. Bruno also stated that the sun was also ‘just’ a star, like all others. This went completely against the teaching of the Church that precisely stated that the earth was the center of the universe, the so-called ‘geocentric model’. The Catholic Church also found it offensive that Bruno claimed that there was something infinite besides God, namely the universe. According to the scientist, there were also countless other solar systems to be found there. However, Bruno himself believed that his scientific views did not conflict with the Bible.
In 1581, thanks to the patronage of the French King Henry III, Bruno was able to publish some scientific works in relative peace in France. He not only wrote commentaries on Copernicus’ teachings and critiques of Aristotelian natural philosophy, but also wrote, for example, a book on memory training ( mnemo technique ) and a comedy: Il Candeloia. Scientifically important were his Dialoghi : three cosmological and moral dialogues about, among other things, the infinity of the universe, the appreciation of the Bible and the relationship between the universal and individual soul.
After his return to Paris in 1585, Bruno soon ran into trouble again. The political climate in France had meanwhile completely turned around, so that the liberal Italian had to walk on eggshells. However, that turned out to be nothing for him. Bruno got involved in all kinds of discussions with Catholic scholars and did not mince his words. In the end, this got him into so much trouble that he decided to move again. In 1585 he left for the German territories for a trip through various university towns. During this period Bruno published several smaller works, including the Articuli centum et sexaginta(1588). In it he spoke out against various modern philosophers and mathematicians and argued for religious tolerance. As far as he was concerned, different faiths had to be able to coexist peacefully.
In August 1591, Bruno accepted an invitation to live in Venice, one of the most liberal Italian states at the time. Presumably, the scholar hoped to secure the vacant chair of mathematics at the University of Padua. This mission failed. The chair went to his famous contemporary Galileo Galilei, who was also persecuted by the Church.

Court case
In 1592 Bruno was arrested by the Inquisition in Venice for allegedly heretical statements. Rome then demanded his extradition. On January 27, 1593, a process began there that would last no less than seven years. During his interrogations, Giordano Bruno insisted that his scientific positions did not contradict the teachings of the Church as far as he was concerned. He further emphasized that he was mainly interested in philosophical matters and much less in theological matters. His interrogators were not satisfied with that. The Church demanded that Bruno completely distance himself from his earlier statements. Among other things, people fell for his statements about the universe, Christ, the Last Judgment and the soul.However, the scholar refused to distance himself from his statements and made it known that as far as he was concerned there was absolutely nothing to deny. Pope Clement VIII officially declared Giordano Bruno a heretic and ordered that he be put to death. When the death sentence was read to him on February 8, 1600, he is said to have responded as follows:
“Perhaps your fear of passing this sentence is greater than mine of hearing it.”
On February 17, he was transferred to the Campo de’ Fiori and burned alive upside down. Exactly why the Church condemned the scholar as a heretic cannot be ascertained, because his file is missing from the archives. A statue has stood on the spot where Bruno died since 1889. Every year on the day of his death, scientists gather here to plead for the scientist’s reparation. A crater on the moon is named after Giordano Bruno.

Some quotes from Giordano Bruno:
“Truth does not change because it is, or is not, believed by a majority of the people.”
“It is proof of a base and low mind for one to wish to think with the masses or majority, merely because the majority is the majority. Truth does not change because it is, or is not, believed by a majority of the people.”
“They dispute not in order to find or even to seek Truth, but for victory, and to appear the more learned and strenuous upholders of a contrary opinion. Such persons should be avoided by all who have not a good breastplate of patience.”
“If the butterfly wings its way to the sweet light that attracts it, it’s only becasue it doesn’t know that the fire can consume it.”
“Unless you make yourself equal to God, you cannot understand God: for the like is not intelligible save to the like. Make yourself grow to a greatness beyond measure, by a bound free yourself from the body; raise yourself above all time, become Eternity; then you will understand God. Believe that nothing is impossible for you, think yourself immortal and capable of understanding all, all arts, all sciences, the nature of every living being. Mount higher than the highest height; descend lower than the lowest depth. Draw into yourself all sensations of everything created, fire and water, dry and moist, imagining that you are everywhere, on earth, in the sea, in the sky, that you are not yet born, in the maternal womb, adolescent, old, dead, beyond death. If you embrace in your thought all things at once, times, places, substances, qualities, quantities, you may understand God.”