Institute and Museum of History of Science, Florence, ITALY
The abhorrence of the void
| Many of the followers of
met with difficulty in reconciling some of the conclusions of the Greek
philosopher with Church dogma. This
is the case, for example, with the Aristotelian thesis of the logical
impossibility of the void. In the thirteenth century, Scholastic philosophers
and theologians debated this idea, in which they saw the denial of divine
omnipotence: if God wanted to, he could, in fact, create a void. They
reaffirmed, though, that it was impossible to produce a void in nature
with "natural" forces.
Developing ideas from the Physics, some medieval authors elaborated the theory of nature's abhorrence of the void: a constitutional horror of the void made nature adapt in any which way to avoid its production.
The theory of the abhorrence of the void was used to interpret various natural phenomena: the difficulty of separating two closely fitting perfectly polished surfaces; the difficulty of opening well-sealed bellows; the refusal of liquid to flow from small holes in the base of a water container whose top is completely closed; and the height limit to which pumps and syphons managed to raise water by suction. The abhorrence of the void was also used to explain why sealed bottles filled with water broke when they froze: it was claimed, wrongly, that when water froze, it reduced in volume, so that nature forced the bottle to break to avoid, as a consequence of this contraction, the creation of a void.