Death is the one thing
Fate gave our kind.
Disdain yourself now, nature, the brute
hidden power that rules to common harm,
And the boundless vanity of all.1
These are the words that Giacomo Leopardi, age thirty-five, addressed to his weary heart in the most desperate of his poems. Not everyone shares this despair, and those who do don’t share it all the time. The infinite vanity of all—which can hardly be questioned—weighs on us only at times of clear-sightedness, and such moments, in a normal life, are not frequent. Besides, if we have the impression (true or false) that our actions are not useless, and that they help to, say, alleviate pain or give pleasure, usually we do not feel unhappy. Further, luckily for us, or our “bright illusion,” there are on this earth dawns, forests, starry skies, friendly faces, and precious encounters, which seem not to be subjected to the brute power.
Yet this power appears indisputable and evident (in other words, not “hidden”) to anyone who has found himself fighting the old human battle against matter. Those who have done so have been able to observe through their own senses that, if not the universe, at least this planet is governed by a force that is not invincible but perverse, that prefers disorder to order, jumble to purity, a tangle to parallelism, rust to iron, a pile to a wall, and stupidity to reason. Against this power (who has not felt it?), which works also within us, we need defenses. Our main defense is the brain, which must therefore be maintained in good condition, but we also possess lesser defenses, entrusted with simpler tasks, that we share with the lower animals and maybe even plants. We don’t need a brain to sweat when it is hot or to contract our pupils before a glaring light; in fact, these are operations that the brain is incapable of performing.
When all these mechanisms—whether or not they are dependent on the brain—work properly, we can preserve the status quo. This happens fairly easily on the scale of days and months, but less successfully on the scale of years and decades, such that we grow old and die. This quality, of self-preservation against the brute power of degradation and death, is typical of living matter and its more or less crude imitations, and it is called homeostasis. It enables us to resist the thousands of changes, internal and external, that threaten to break our balance with the environment.
Of course, it hasn’t been demonstrated nor is it demonstrable that becoming other, relinquishing our identity, is always a bad thing. Whether it is or not depends on the initial quality of that identity, and on how it is subjectively perceived. There are individuals who spend their entire lives obsessed and saddened by the desire to change their skin, because (maybe wrongly) they are not satisfied with the skin they live in, and who can’t change because of an excessive homeostasis. This, however, is a rare occurrence. In general, in the long run, homeostasis fails: “life” makes sure that we become someone else—fearful, idle, stingy, corrupted, or hypochondriac. By gnawing away at our defenses, it destroys them. In most cases, “life” changes us for the worse, and so homeostasis, although essentially conservative, is a good thing. Naturally, progress, reforms, innovations, inventions are also good things, but their pursuit is not for everyone, while self-preservation is a minimum requirement for all living beings.
Not only living beings. It is important to note that the devices intended to keep constant one or more variables of a process originated with the industrial age, and, more precisely, with the engine. As early as 1787 James Watt had added a centrifugal governor to ensure a constant speed for his first steam engines. It was a small vertical shaft connected to the engine by a pair of conical gears. Two opposing, rigid pendulums were suspended from it; joined to them was a system of tie-rods that controlled the steam valve. The faster the rotation speed, the higher the pendulums rose, owing to centrifugal force, and the more constricted the valve became. Thus an equilibrium was reached—that is, a steady speed regardless of the load. In this manner, long before the concept of homeostasis was theorized, Watt had achieved what two centuries later was to be called a “feedback loop”: it is a “loop” because it has to do with powering the system. A classic example of feedback is the simple one of water heaters. The heater includes a thermometer that not only measures the water temperature but compares it with a temperature set by the user; it interrupts the current supply if the first temperature is higher than the second. In this way we obtain an “all or nothing” adjustment that is rather rudimentary; inertia within the system is such that the temperature, rather than remaining uniform, varies within four or five degrees. This is acceptable for bathwater (which, moreover, may be mixed at will with cold water), but it is not acceptable in many other circumstances requiring deviations of less than one degree, or even one hundredth of a degree—for instance, when we have to measure with precision a chemical or physical property that depends heavily on temperature.
In these cases, we rely on refinements very similar to what happens in living organisms and to what empirical experience has suggested to man from time immemorial. An adjustment can be modulated—that is, the correction can be proportional to the observed variation. The thermostat of the water heater can be compared to a helmsman who can hold the rudder only in its two extreme positions, hard left or hard right. A good helmsman would not act this way; rather, consciously or not, he would adjust the rudder in accordance with the deviation from the course shown by the steering compass. The first helmsman will follow a winding line; the second, a line that is almost straight.
We can rely on even subtler expedients. The adjustment can be achieved not through the attainment of the prescribed target value but through the speed at which that target value is pursued. In the case of the thermostat, the trigger is the speed at which temperature increases or decreases. Principiis obsta, the instrument intervenes at the beginning; it has been taught to look ahead and take action “like a good father.” If the temperature rises rapidly, the thermostat “foresees” that the maximum target value will soon be exceeded and interrupts the energy supply before this happens.
There are other cases where the target value (highest or lowest admissible) of the parameter to be regulated depends on its duration. For instance, a sick person can withstand a fever of 105 degrees Fahrenheit for some minutes, 104 degrees for a few hours, and 103 degrees for a few days. Similar situations (where “what cannot be achieved by heat is achieved by time”) are frequent in chemistry and also in cooking, which is a more complicated and less transparent sort of chemistry. For this reason there are controls that take into account the time that passes and what happened earlier. In fact, the most advanced instruments can be programmed to work in the “all or nothing” mode, in the modular mode, to react to the speed of change, to its progression over time, or in various combinations of these four modes. It is even more surprising, perhaps, that the workmen who are in charge of controls often learn how to program their instruments in the most suitable way for the required activity, even though they have no understanding of how such instruments function. In the same way, we learn to ride a bicycle even if we do not know the theory of the gyroscope.
It has been the dream of politicians of all eras to devise tools for homeostasis that would enable them to maintain the health, or at least the survival, of the regime they believe in. However, human societies are so complex, the parameters in play so many, that this dream will never come true. Fifty years ago it used to be said that too much freedom leads to tyranny, and that a tyranny too harsh leads back to freedom. If this assertion were applicable in general, one could recognize in it a fluctuation around a point of equilibrium—that is, a rudimentary regulatory mechanism, however cruel, costly in human lives, and unbearably slow. Unfortunately, what happens in today’s world persuades us to conclude that the assertion is false. Today’s tyrannies tend to hold on indefinitely, like a sort of sclerosis, and surrender only if upset by military intervention or overcome by another tyranny. Too much freedom, that is, license, does not breed tyranny but becomes gangrenous. Our current malaise originates in this: we no longer perceive restraining forces, homeostasis, and feedback loops. The world seems to be moving forward toward an unspecified catastrophe and we can only hope that its progress is slow.
Notiziario della Banca Popolare di Sondrio, no. 33, December 1983
1. Giacomo Leopardi, “A se stesso” (“To Himself”), translated by Jonathan Galassi.