The Great Conversation: Space
By Gabriel Blanchard
A deceitfully simple concept, space has prompted extensive analysis in philosophy and the sciences alike.
We are sufficiently used to space, due to being in it so often, that few of us think about it much—except perhaps when trying to move a piece of furniture through a door. In a sense, this is the beginning of the first major way that space has become one of the great ideas, namely through geometry. Shape, angle, measurement, and proportion all describe things in terms of space, laying a groundwork for architecture and physics among other disciplines.
Perhaps inspired by the magnificent Athenian architecture that surrounded him, Plato helped inaugurate the career of space in philosophy. In the Timaeus, a dialogue discussing the creation of the physical world on the pattern of the Forms, he seems to equate space as a “receptacle” with prime matter, the formless stuff out of which all bodies and even the classical elements themselves were thought to be made. Centuries later, St. Augustine interpreted Genesis 1.2’s statement that “the earth was without form and void” as an allusion to this raw material. Whether space was, independently, a thing became a regular matter of debate. One of the stock questions for logic students at Medieval universities was, “Can God create a vacuum?”—because of course a vacuum is defined precisely by not being anything, unless sheer empty space is a thing. But if it is, what is it? How do you define it?
The Medieval world also saw experiments in creating vacuums as a way of understanding space, both in Europe and the Arabic world. As early as the tenth century, the Muslim scholar Al-Farabi had determined that air expands to fill available space, and therefore argued (in line with Aristotle) that a perfect vacuum was an incoherent concept; in the fourteenth, Jean Buridan, an influential rector at the University of Paris, reported that a pair of teams of ten horses each could not pull open a set of bellows while the port was closed. The laws of nature and of nature’s God, it seemed, abhorred a vacuum.
Later scientists took differing views. Atomists like Newton and Locke understood matter to be made of individual units separated by empty space—an idea that persists, in a highly modified form, in modern physics. It was partly the Enlightenment understanding of space that led to the possibility of the universe being infinite, but curiously enough, the finite universe has made a comeback too. Einstein wrote that “According to the general theory of relativity, the geometrical properties of space are not independent, but are determined by matter.” It is for this reason that we can speak of the universe, the all-embracing object with no adequate standard of comparison, as getting bigger.
St. Thomas Aquinas, Summa Theologiae Part I, Question 66
Albert Einstein, Relativity: The Special and General Theory