Sidonius Apollinaris, who died in 489 A.D., was a diplomat, literary figure, and ecclesiastical official of fifth-century Gaul. He was also a letter-writer of impressive fecundity and erudition; and his powers of memory were so great, we are told, that he was able to recite long liturgies from memory and deliver orations without notes or preparation. One of his letters (II.10), written to a friend named Hesperius, contains the following noteworthy sentence:
So press on, and do not deprecate your literary work because of the opinion of the uninformed masses—for nature has decreed that in every art, the grandeur of acquiring knowledge gains in impressiveness as it becomes rarer. 
Sidonius was trying to encourage his friend to persist in his reading. He thought that one’s reading should be continuous and without limit, and that a reader should not look for excuses to deflect himself from productive studies. Marriage and family were no excuse for shirking this obligation, for sincere students find in marriage “an opportunity for literary study, while sluggards see only a pretext for avoiding it.”
What is true with regard to study and writing, is true in so many other areas of endeavor. The sincere seeker will not allow himself to be deflected from his path by the transient opinions of the mob. He will learn that chasing after fame and money is exhausting, degrading, and ultimately futile; and he will gradually come to realize that what brings peace of mind, and true freedom, is the pursuit of worthy goals for their own sake. How can anyone who hopes to achieve anything good pin his hopes on the fickle opinions of the crowd? The artist, the reformer, the writer, the genuine seeker: he acts from an inner impulse, and is animated by a flickering light bequeathed him by nature at birth. As Cicero says (Tusc. Disp. III.6),
Non enim silice nati sumus…
Which means, we are not born from rocks. We are creatures of flesh and blood, motivated by nature’s pristine designs, and capable of the loftiest sentiments. Was it for money that President Theodore Roosevelt, that supremely great leader, risked his life floating down an unknown river in the wilds of Brazil? Were the great explorers of history driven by dreams of financial windfalls, or were they goaded on by a supremely creative instinct to break through barriers, overcome obstacles, and touch the face of the Great Unknown? Was it for money that the great sculptors, artists, writers, poets, and scientists obeyed the stirrings bequeathed to them by nature?
Consider the explorations of naturalist Alexander von Humboldt in South America. From 1799 to 1804, he trekked through the wilds of the continent, taking measurements, collecting samples, and observing natural phenomena that no European had seen before. He was possessed of a passionate energy to know, to understand, and to comprehend; and he was one of the first modern scientists to think of the universe as an organic whole. It is no accident that he titled his masterwork Cosmos. One bizarre incident that took place during his travels in the region now covered by Colombia and Venezuela tells us much about his pure lust for knowledge and understanding.
In March of 1800, Von Humboldt and his party left the valleys of Aragua, a region in what is now Venezuela, and began to ascend the mountains that stretch towards La Palma. They eventually descended into the Llanos Basin, which is located in northeastern Colombia; from here they made their way to the Apure, in the province of Varinas. When they crossed the Mesa de Calabozo, the sun was so ferocious that they had to insulate their hats with rhopala leaves to protect themselves. It was in Calabozo that our travelers learned there were electric eels in the area; and Von Humboldt, long fascinated by this mysterious animal and its legendary capacities, could not resist the chance to make a detailed study of the eels. These fearsome creatures, known as gymnoti, inhabited the stagnant ponds and pools found along the Orinoco River.
Trying to study the eels meant risking his life. Electric eels can deliver charges in excess of 800 volts, an amount easily fatal to a man; he had no insulating equipment of any kind, no tools to capture the creatures, and no real understanding of the extent of their powers. What Von Humboldt did have was passion and imagination, and that was enough. On March 19th, near the village of Rastro de Abaxo, he and his Indian guides found some suitable pools to explore. Taking the advice of the natives, Von Humboldt first tried to throw toxic plants into the water to attempt to incapacitate the eels, and render them vulnerable; this effort proved unsuccessful, as the eels buried themselves in the mud at the bottoms of the pools. The natives then suggested that they drive some wild horses into the water, and hope that their movements would force the eels to rise to the surface. What happened next is described by Von Humboldt in a startling and unforgettable passage:
The extraordinary noise caused by the horses’ hooves makes the fishes issue from the mud, and excites them to combat. These yellowish and livid eels, resembling large aquatic snakes, swim at the surface of the water, and crowd under the bellies of the horses and mules. The struggle between animals of so different an organization affords a very interesting sight. The Indians, furnished with harpoons and long slender reeds, closely surround the pool. Some of them climb the trees, whose branches stretch horizontally over the water. By their wild cries and their long reeds they prevent the horses from coming to the edge of the basin. The eels, stunned by the noise, defend themselves by repeated discharges of their electrical batteries, and for a long time seem likely to obtain the victory.
Several horses sink under the violence of the invisible blows which they receive in the organs most essential to life, and, benumbed by the force and frequency of the shocks, disappear beneath the surface…In less than five minutes two horses were killed. The eel, which is five feet long, presses itself against the belly of the horse, and makes a discharge along the whole extent of its electric organ. It attacks at once the heart, the viscera, and the cæliac plexus of the abdominal nerves. It is natural that the effect which a horse experiences should be more powerful than that produced by the same fish on man, when he touches it only by one of the extremities. The horses are probably not killed, but only stunned; they are drowned from the impossibility of rising amid the prolonged struggle between the other horses and eels.
Von Humboldt was able to capture five large gymnoti by using small harpoons fastened to cords made of plant material. All of them were around five feet, four inches in length; one of them weighed over fifteen pounds. In handling the eels, no metal of any kind could be used. Von Humboldt performed various experiments (using himself as the subject) to evaluate the electrical power that the eels could generate. He found that even when dead, the bodies could deliver strong charges over significant distances; he even touched various parts of the eels to experience the shocks himself.
In his desire for knowledge and understanding, he was prepared to take risks that few others were able or willing to tolerate; and yet he assumed these risks because he had to, because he understood that this was his life’s mission. He was that rare seeker after knowledge, that chiseler of marble who fashions, through his own unrelenting labors, a grand and vibrant sculpture. It is just as Sidonius said in his letter to Hesperius: the grandeur of acquiring knowledge gains in impressiveness as it becomes rarer. Be driven by what you were designed by nature to do. Do what you must do, not what you believe will gain you temporary profit. He who bases his actions, and his path, on the illusory inducements of this world, will find himself abandoned by them in his hour of need. Know, brother, that only true virtue–that obedience to the commandments of our divine nature–is permanent and eternal. This, then, must be our task: to take up that chisel, that hammer, that brush, or that pen, and manifest in physical form the full spectrum of nature’s unique light emanating from our souls.
 Igitur incumbe, neque apud te litterariam curam turba depretiet imperatorum, quia natura comparatum est ut in omnibus artibus hoc sit scientiae pretiosior pompa, quo rarior.
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