Today we continue our study of how the statement, “I am a woman trapped in a man’s body” (Carl R. Trueman, The Rise and Triumph of the Modern Self, p. 19), came to be taken seriously by millions of intelligent people. The previous essay explained why no one before 1500 could have comprehended the modern dichotomy between the external appearances of such things as the male and female bodies and their internal reality. At the conclusion of that essay, I promised that in the next part “we will see how the architects of the scientific revolution—Galileo, Bacon, Descartes, et al.—destroyed confidence in the reality of forms and souls and replaced them with atoms, space, and machines. The appearances no longer reveal the reality of things. Creation is emptied of spiritual reality, meaning, purpose, moral law, and beauty, all of which are transferred to the inner subjective world of the human mind.” We begin that saga with Galileo Galilei.

Galileo Versus Aristotle

Students of nature before Galileo assumed that the way things appear to us reveals something about their inner reality and that the inner reality of things manifests itself truly in their external appearances. The meaning, purpose, beauty, moral law, and value we experience in our minds also exists in nature. The goal of Aristotelian science was understanding how all these qualities are embedded in the natures of the things themselves. However, by the time Galileo (1564-1642) came to maturity in the early seventeenth century, such thinkers as Francis Bacon (1561-1626), Rene Descartes (1596-1650), and Johannes Kepler (1571-1630) were already complaining that the doctrine of forms contributed nothing to our empirical understanding of things. Mysterious forms, whether they are real or not, cannot be clearly thought and have no value for making predictions, discovering laws, and creating technology. And for reasons I do not understand, achieving these goals had become the driving force of the emerging scientific revolution.

Galileo and the Mathematization of Nature

Galileo believed that applying mathematics to nature was the only way to achieve his practical goals. Numbers and mathematical operations are clear and simple, and when we see the value of a mathematical expression or equation, we become certain of its truth. To understand nature, argued Galileo, we should set aside questions about its mysterious inner nature, the ways it appears to us, and the way it makes us feel; these are irrelevant to achieving the goals of the new science. We will then be free to work out the mathematical laws of nature’s movements and transformations. At last, we can understand nature as clearly as we understand mathematics!

Unforeseen and Unintended Consequences

To modern ears, Galileo’s philosophy of science and his revisions to the scientific method sound familiar and innocent. Whatever Galileo’s intentions, however, his innovations produced a profound moral and religious revolution. For by limiting science to knowledge that can be expressed in mathematics, Galileo, Descartes, et al, broke decisively (1) with the traditional belief that things reveal their inner reality in their outward appearances, and (2) with the corresponding belief that the inner worlds of things in nature are intelligible and mindlike in a way similar to the inner world of the human mind.

The Distinction Between Primary and Secondary Qualities

Perhaps Galileo and other pioneers of the scientific revolution could have narrowed science to what can be understood in mathematical terms without postulating an alternative to Aristotle’s intelligible forms as the cause of the way things appear to us. But they did not exercise such restraint. Instead, they replaced Aristotle’s inner forms and souls with imperceptible material atoms or corpuscles, which possess only mathematically measurable properties: shape, movement, mass, velocity, etc. In ways Galileo and Descartes cannot explain, these material particles cause us to experience the world in a human way. By distinguishing primary qualities (material, mechanical, and mathematical) from secondary qualities (psychological, organic, and qualitative), they drove a wedge between the way human beings experience the world and the world as it is apart from human perception. The only bridge between the two is mathematics. Listen to Galileo, Descartes, and Locke drive this point home:

“To excite in us tastes, odors, and sounds I believe that nothing is required in external bodies except shapes, numbers, and slow or rapid movements. I think that if ears, tongues, and noses were removed, shapes and numbers and motions would remain, but not odors or tastes or sounds. The latter, I believe, are nothing more than names when separated from living beings, just as tickling and titillation are nothing but names in the absence of such things as noses and armpits” (The Assayer, 1623).

“The properties in external objects to which we apply terms light, color, smell, taste, sound, heat and cold—as well as other tactile qualities…are so far as we can see, simply various dispositions in the shapes, sizes, positions, and movements of their parts which make them able to set up various kinds of motions in our nerves which are required to produce all the various sensations in the soul” (Descartes, The Principles of Philosophy, 1644; Quoted in Cottingham, A Descartes Dictionary, p. 149).

“These I call original or primary qualities of body, which I think we may observe to produce simple ideas in us, viz. solidity, extension, figure, motion or rest, and number. Secondly, such qualities which in truth are nothing in objects themselves but powers to produce various sensations in us by their primary qualities, i.e. by bulk, figure, texture, and motion of their insensible parts, as colors, sounds, tastes, etc. These I call secondary qualities”(John Locke, Essay Concerning Human Understanding, 1698, II. 8)

Oh Galileo! What Hast Thou Wrought?

Galileo convinced the world that the variety and obscurity of the natural order could be reduced to the clarity and certainty of simple mathematical equations. Modern advances in understanding the mathematical laws of nature and the explosion of technological innovation rely on this supposition. But at what cost?  God’s glorious creation has fallen silent, emptied of spiritual reality, meaning, depth, mystery, purpose, moral law, and beauty, all of which have been transferred to the inner subjective world of the human mind. But how can we continue believing in the reality of meaning, depth, mystery, purpose, moral law, and beauty, if we think of them as existing only in the human psyche? They seem to be hanging in midair with no confirmation in common experience or foundation in an enduring reality.

Aristotle and all the ancients believed in the likeness and harmony between the human world and the natural world. This belief seemed reasonable, obvious even, because humans are part of the natural world. Galileo, Descartes and others split them apart, dividing the qualities we experience into the objective (real) and subjective (psychological) spheres. Human beings became islands of mind in a sea of mindless matter. It was inevitable that this division would become intolerable…that the human mind and soul would be reunited to nature by reducing them to something simpler. Sooner or later some thinker would do to the human soul what Galileo had done to the solar system.

And that “someone” was John Locke.