Galileo Galilei lived from 1564 to 1642. A great Italian scientist, he was the originator of modern physics. Many scientists believe that Galileo's work was plainly ‘true’, and that through the power of his intellect and logic he was able to supplant the erstwhile Aristotelian view of the world with a new, mathematical one. The view of succeeding generations was to seek objective truth, but this is not how it happened.
Galileo was a great innovator and truly one of the great imaginative heroes of human history. However, his theories came to be accepted not primarily on the basis of the strength of his thought and observation, but on abstraction, a new language, the question of empirical validation. Galileo published a number of articles in the early 17th century strongly supporting the Copernican theory that the earth circled the sun (heliocentrism). These ideas were seen by church authorities as profoundly disruptive of the existing intellectual status quo and the church's teachings – and they therefore had a wide set of social implications. From the time Galileo wrote The Starry Messenger in 1610 the church took steps to shut him up and he was subject to harassment from the authorities (especially the ecclesiastical authorities) for the rest of his life. The authorities understood that the new ideas Galileo was writing about were dangerous, that his propositions were mere representation of objective facts, but that they carried profound, potentially uncontainable social implications for political authority.
In 1633 Galileo was tried before a formal inquisition for promoting the views of heliocentrism. He was found guilty, placed under house arrest for the rest of his life, and made to recant. They showed him the instruments of torture and told him to imagine what would happen if he did not recant. They knew their man and this was all they needed to do. Galileo recanted, even though he continued writing in secret and was able to arrange for his manuscripts to be smuggled to safety, where they were subsequently published.
Today's school students are taught that the strength of Galileo's theory lay purely in the fact that, compared to the Aristotelian orthodoxy, it carried greater empirical validity and was more closely in accord with objective reality. In reality, the opposite was the case. Galileo's theory – at least in its early stages – was actually empirically inferior to the Aristotelian system. Everyone knows, after all, that the first law of motion – that a body in motion tends to remain in motion – is never borne out in fact. Rather, the Aristotelian idea of inertia – that if you push a body it will stop – is what we observe on earth in every real instance. In reality, Galileo's theory was not empirically valid. It was abstract and contrary to the facts. Indeed, this was its great innovation. Galileo discovered not the concept of empirical science, but a new idealised language, the language of mathematics, in which the empirical questions could be formulated. The success of the theory was dependent not on its ‘objective’ validity, but on other factors related to knowledge, philosophy, society and politics.
Galileo was attacked, but he fought back in his writings. He took the struggle to the streets, writing popular works, not just in Latin, but also in Italian, the language of the common people. In a book on the arguments for and against heliocentrism (Dialogue Concerning the Two Chief World Systems) he sought to obtain the support not of the effete intelligentsia, but of the common people. There are two main characters in the book: Sagredo, who is Galileo himself, and a second person called Simplicius in Latin or Simplicio in Italian, who represents the Aristotelian view (that the sun revolved around the earth) and speaks in phrases used by the Pope. The name Simplicio in Italian has the connotation of a simpleton, and the portrayal of this character served to cast greater doubt on the established ideas amongst the local readers of the book and ensured readers were on Galileo's side.
Galileo's struggles to get his ideas accepted show how science, culture and society are intertwined. They draw attention to the fact that the success of a scientific theory – its acceptance or rejection, its capacity to generate approval or hostility – is not determined merely by its philosophical or empirical value, but also crucially by the complex social and political frame within which it is embedded.
Scientific meanings are subject to and dependent on social attitudes, prejudices and belief systems. People can find ways to convince themselves that a particular view is true depending on their personal attitudes. It is not the case that the process of understanding science, data and the world, is detached and objective. It is always rooted in local vested interests. Science and medicine cannot be separated from the contemporary cultural debates. This is the essence of what Galileo discovered. The success of a theory depends on social struggles, which can be ruthless and even violent. In Galileo’s case, he fought hard and, despite the setbacks, was eventually victorious, even if in his case the full victory came only posthumously.