In 1610 Galileo (1564-1642) peered through his small 20 power telescope, and saw moons around Jupiter, observed phases of Venus (like the phases of the moon) and observed craters on our moon. This played a major role in the intellectual crisis of his day: the collapse of Aristotelianism.
Aristotle’s (384–322 BCE) M.O. (modus operandi) was to start with what he thought were reasonable premises, and by deduction alone determine how the Cosmos worked. For over a millennium Europe’s science and theology rested on two fundamental pillars: revealed Scripture and Aristotle.
During the Middle Ages in particular, the [Catholic] church embraced Aristotle and his approach. However, by Galileo’s day, cracks were beginning to appear: Aristotle asserted that the heavenly bodies were perfect; Galileo looked through his telescope — uh oh, there are craters on the moon — it’s not perfect! Aristotle also taught that the Earth was the center of the Cosmos: uh-oh, Jupiter’s moons clearly did not move around the Earth like all heavenly bodies were supposed to, but instead orbited a mere planet — maybe the Earth is a mere planet too. The phases of Venus were also strong evidence that Venus orbited around the Sun and not the Earth. If Aristotle were wrong about these, what else was he wrong about?
A lot, as it turned out. So with cracks in Aristotle’s physics piling up, scientists and philosophers set about creating a new theory of how the Cosmos worked, and a method by which this kind of fundamental error couldn’t happen again.
Much progress was made, but the philosopher who put all the pieces together and arguably founded modern science and philosophy was René Descartes (1596-1650).
You’d think Descartes came up with his ideas after calm, rational analysis and deduction. But no: they are the result of a night of intense, almost mystical dreaming! On the night of 10–11 November 1619, Descartes shut himself in a room with an “oven” to escape the cold. In the week prior, Descartes recounts how he felt a mounting sense of ‘enthusiasm’ — from the Greek word ENThOUSIASMOS meaning “having the being of god within” — in ancient times usually possession by the god Apollo. In Descartes’ day ‘enthusiasm’ was still not considered a good thing — indeed in the witch trials, ‘enthusiasm’ was considered a symptom of possession. (We’ve watered down the concept considerably!) On the night in question he had three dreams, in which he believed a divine spirit revealed to him a new philosophy.
Descartes’ accounts of his dreams are quite detailed, so I can only provide the barest of outlines: in the first dream he encounters ghosts, and winds blowing so hard he has to walk leaning to one side while everyone else is walking upright, and it continues from there. In his second dream he hears a loud thunderclap which wakes him up. His third dream was the most elaborate: he finds a dictionary on a table, and a book of poetry. Descartes notices a man who presents him with a piece of a verse, beginning with the phrase “Yes and No”. Descartes knows the poem, and sets about finding it in the poetry book. Meanwhile the dictionary and book of poetry disappear and reappear in different positions. Descartes isn’t able to find the poem after all, but says to the man that he knows a better one, and sets about finding it. The man disappears, and — this is the really strange part — in his dream Descartes realizes he is dreaming and analyzes the dream — while dreaming! The poems are real poems (in the ‘real world’). Descartes’ analyses of his dreams and their poems — asleep and awake — apparently provided him with the key insights he needed to build his Rational Philosophy.
So with Descartes we have Rational Science coming into being from a night of intense dreams, which is certainly not “rational inquiry and deduction.” It would seem that strange imaginations from the depths of the human psyche played a decisive role even in the founding of Modern Science.
Browne, Alice. “Descartes’s Dreams.” Journal of the Warburg and Courtauld Institutes, vol. 40, 1977, pp. 256–273. JSTOR, www.jstor.org/stable/750999. Accessed 15 July 2021.
Keevak, Michael. “Descartes’s Dreams and Their Address for Philosophy.” Journal of the History of Ideas, vol. 53, no. 3, 1992, pp. 373–396. JSTOR, www.jstor.org/stable/2709883. Accessed 15 July 2021.