Born Neils Stensen in late 17th century era Denmark, today Nicolas Steno is immortalized by many as the founder of modern geology and specifically modern stratigraphy, along with inducing a change in the way of scientific thinking emphasizing on empiricism over logic and past theory. He never referred to Aristitolean metaphysics or Cartesian deductions but rather believed in what results his experiments produced, advancing with that evidence while negating other pre-defined laws. Steno understood the deep connection between Earth, life and understanding, proving the philosophical belief of holism in his experiments.
The son of a goldsmith, Nicolas Steno grew up to be an anatomist and found a duct in animal skulls that delivered saliva to the mouth, now known as the salivary duct. He refuted René Descartes, that only humans had a penial gland, proving it wasn’t the seat of the soul, which was inarguably the debut of neuroscience.
In his endeavors of cutting up different species of animals, he was once approached by the Grand Duke of Tuscany to dissect a shark whose teeth resembled tongue stones: odd rocks spotted in Malta and the mountains near Florence. Phinly, an old Roman naturalist, argued that they fell from the sky while the people from the Dark Ages said they were snake tongues. Steno saw that they were neither, but shark teeth composed of the same structure as the teeth were. The shark teeth had fallen onto the ocean floor from ancient sharks and in time the watery sediment has washed away leaving way for layers of earth to cover the teeth in the order of oldest to newest. This way Steno deduced that the fossils of extinct species would be older as they went deeper into the earth. Through his shark experiment, he had founded modern geology and stratigraphy, the study of the layers of rocks.
Steno's sketch of the shark head and teeth (1667). Image obtained and adapted from Wikimedia Commons.
This methodology gave way to an even greater thought, uniformitarianism, that the Earth’s present observable state was, in general, influenced by processes of the past. A revolutionary thought back then, this meant that any unevenness in the layers of rock were from after the last layer had accreted, from wind erosion and other natural forces. Maybe a process still active today caused a change not just in rocks but in life as well.
Nicolas Stena has been quite unknown despite proving with his experiments that empirical evidence always overruled intellect and deepened the perspective. He produced perhaps the most groundbreaking results with his experiments and laid the seeds for development of science while staying connected to his philosophy. His maxim was his search for truth beyond our comprehension of the beauty as of yet unknown as was his saying, “Beautiful is what we see, more beautiful is what we know, most beautiful is what we don’t.”