Johannes Kepler, the German mathematician who formulated the three laws of planetary motion (a foundation for Newton's ideas later on), is my hero. I am in the middle of a biography on him, and though I don't think it is particularly well-written, I am enjoying it nonetheless because Kepler is an interesting character. What impresses me the most is not his genius but the way in which he approached thinking. Whether it was a theological, scientific, or philosophical issue, he approached it with an open mind and a keen sense of truth.
He was a devout Lutheran, and attended seminary to become a preacher and theologian. But he never just towed the party line. He was critical of both Catholics and Protestants on various issues, pointing out where each had gotten something wrong. Most of his close friends and colleagues would reject any view or opinion from a Catholic, but Kepler would aggravate them to no end by highlighting parts of the Catholic position that he thought were true. This kind of talk, as well as criticism of certain doctrines of Lutherans, resulted in Kepler being excommunicated from his own religious group. Later, in the midst of the counter-reformation, despite intense pressure (and danger) Kepler refused to abandon his core Lutheran beliefs to appease the angry Catholic authorities. His nuanced view of truth and theology was a rarity in the 16th century. Kepler was a non-partisan voice in the midst of the crazy religious wars of his time.
Kepler's Lutheran approach to science may have also helped him break from long-held assumptions about the universe. Theologically, Luther suggested stripping away centuries old dogma and established interpretation to allow the individual to read the Bible for themselves and form their own interpretation. In science, Aristotelianism had long dominated how the world worked and how the heavens were arranged. Kepler, though, didn't just accept this dogma and work within its framework; he approached the heavens too with an open mind. He was a Copernican (Copernicus was the canon law priest in the Catholic church who suggested the planets revolved around the Sun rather than the Earth) when few were, and went on to formulate cosmological laws which went against the received Greek wisdom. Kepler's willingness to seek truth whether or not it went "against the grain" led to scientific work that became a huge stepping stone to modern cosmology.
Kepler was also a neo-platonist, obsessed with mathematical beauty and harmony (so was Copernicus). Kepler thought that he could discover God's laws and the underlying harmony of the universe; this, and his exceptional mathematical gifts, are part of the reason why he ultimately pursued science instead of theology. Kepler saw his science as a branch of theology; the study of the order God had put in his creation. Kepler's story runs straight against our own received wisdom that science and theology are opposed and that religious belief is incompatible with science or scientific discovery. On the contrary, religious convictions were a primary motivation for men like Kepler (and Newton) to study the universe. Both saw themselves as uncovering the mathematical secrets God had used to make the universe run.
Kepler's intellectual approach to difficult or contentious issues is one I hope to emulate. Rarely is one person or one person's viewpoint entirely correct (including our own); we would be better off if we could admit this and, like Kepler, keep an open mind while searching for truth.