21: Nothing, the Ultimate Softener

Cyrano is whiling away the time in captivity as a prospective mate for the Queen’s pet monkey. That seems to be the fate of such unconventional people as astronauts and avant-garde scientists. Meanwhile, he gets an earful from the Spanish physicist...

“But you will ask why gold, iron, metals, earth and wood descend more quickly toward the center of the earth than a sponge. Isn’t the sponge full of air, which naturally tends upwards? That’s not the reason at all, and I say here’s why: a rock may fall more rapidly than a feather, but both are inclined to fall. A cannonball, for example, would fall more rapidly into a hole leading to the center of the earth than a balloon would. The reason is that the metal is a lot of matter compressed into a small volume, and the air in the balloon is a small amount of matter in a relatively large volume.

“The particles of matter in iron are intermixed with each other and are heavier because they are squeezed closely together. Thus, many particles outweigh the few that oppose them. A parcel of air equal in size to the cannonball is not equal in mass. Air yields to the pressure of people moving through it because people are more massive; it thus parts to make way for them.

“I won’t prove this by formal logic, but how do you think a spade, sword or dagger wounds us? Because the metal is a form of matter in which the particles are closer and more tightly bound together than those of your flesh. The metal forces flesh to yield to strength, just as a galloping squadron penetrates a battle line that is of much greater extent.

“And why is a piece of hot metal hotter than a piece of burning wood? Because the metal contains more heat in a smaller volume. The particles in the metal are more compact than those in the wood. Since wood is very porous, it contains a lot of empty space; and the space, being but the absence of matter, cannot be susceptible to heat.

“But, you may object, you suppose empty space as though you had proved it. That’s what we’re arguing about. Well, then, I’ll prove it to you. It’s as complicated as untying the Gordian knot, but I have arms strong enough for an Alexander the Great.

“The ignorant man who thinks he’s smart only because he has a diploma has to answer me. Suppose there is only one form of matter, as I think I’ve shown well enough. How come it yields and compresses as it does? How can a piece of dirt condense into a pebble? Do the particles of the pebble nest one inside the other? Where there is a grain of sand, are there other grains of sand inside it? No, that can’t happen, because two bodies cannot coexist in the same space. The particles of matter have to condense and, if you will, compress by filling the empty space between them.

“Do you say it is incomprehensible that there is nothingness in the world and that we are partly composed of nothing? Well, why not? Is not the whole world enveloped by nothingness? Since you concede that point, admit as well that it is just as easy for the world to have nothingness within as without.

“I see that you are going to ask me why freezing water bursts the vase that contains it unless it’s to prevent a vacuum from forming. But I answer that air presses down on it from above, being drawn to the center of the earth just like solids and liquids. On the way, it finds a vacant room and lodges there. If air finds the pores of the vessel — that is, the ways that lead to this empty chamber — too narrow, too long and too winding, it satisfies its impatience by breaking it in order to find its resting place.

“But without stopping to answer all objections, I dare say that if there were no empty space there would be no motion. Either that one has to admit the interpenetration of matter. It would be too ridiculous to think that when a fly pushes against a parcel of air with its wing, the air makes another parcel of air retreat, and then another, and that the movement of a flea’s little toe might create a hump of air on the other side of the world.

“When stumped, those who object resort to rarefaction. But how do they think that a body can be rarefied or a particle of mass move away from another particle without leaving empty space? Mustn’t the two separating bodies have been at the same place at the same time and thus all three have interpenetrated one another? I expect you will ask me how a pipette, a syringe or a pump can make water rise, when water is not inclined to do so. But I will answer that it is forced to, and it is not a horror of a vacuum that obliges it to turn from its course. Rather, it is joined imperceptibly to air, and it rises when the air embracing it is pulled up.

“That is not very hard to understand when you know the perfect circle and the delicate linking of the elements. When you consider this lime that marries earth and water, you will find that it is neither earth nor water any more; it is the intermediary of a contract between those to enemies. Water and air send each other mists that adapt themselves to each other’s moods and reach a peaceful settlement. Air is reconciled with fire by means of an mediative exhalation that unites them.”

At this point, the physics lecture breaks for dinner. For someone who knows nothing of atoms, molecules or the periodic table, the Spanish physicist is not doing too badly; for one thing, he assumes correctly that a vacuum lies beyond Earth’s atmosphere. Of course, he still has some problems: If he’d thought about cannonballs and balloons falling in a hard vacuum, he might have reached different conclusions. Saying that air pressure causes ice to expand is understandable at a time when the principles of crystalline formation were unknown. Implying that a vacuum plays no part in hydraulics seems to undermine his own argument in favor of the void. The “mist” effect in the formation of concrete and the “reconciliation” of air with fire are further examples of circular reasoning, but they at least constitute an admission of something unknown, namely chemical reactions. One thing he does invent: the “butterfly effect.” However, it has nothing to do with chaos theory; it’s intended as a ridiculous example to prove the necessity of the “void”: insects couldn’t fly if they had to move the Earth’s entire atmosphere to do so. The notion of empty space, or the vacuum, was a contentious one in the 17th century because it was so counter-intuitive. The main thrust of the lecture is to show that it must exist, because matter varies in degrees of hardness and softness. If you wanted to prove to Descartes that a vacuum does exist, how would you do it? Remember, you must use the materials of his time and language he will understand.