Presidential address prepared to be read before the American Historical Association, at Cleveland, December 28, 1918. The annual meeting was not held that year due to the influenza pandemic, and all officers of the Association served until the next annual meeting in December 1919. Published in the American Historical Review 24, no. 2 (January 1919): 183–195.

Vagaries of Historians

Man has an instinctive curiosity concerning processes; though he has been baffled a thousand times in his search for ultimate causes, he turns eagerly to watch causes unfold. If he can not discover the why of things, he can observe with the utmost accuracy the how of things; and possibly he may be able, after a sufficiently ample investigation, to deduce the why from the how. The reason may be indirectly disclosed by the process.

There is another instinct strong in man, and that is his instinct for certitude. He does not rest tranquil amid doubts. The missing link in a chain of evidence or argument torments him, and if he can not find it, he busies himself in imagining what it ought to be like.

These two instincts have never been more active than during the last half century. You have only to glance through an approved history of the literature of any country in order to see with what perfect precision and assuredness the work is done. The sequence of cause and effect rolls on as smoothly as does the leather belt which turns the wheels in a factory. There are no gaps, no doubts, no hesitation. Take the history of American literature, for example, and see how simply Washington Irving is “accounted for”, and then how naturally William Cullen Bryant followed him, and when you come to the New England School, how Emerson, and Hawthorne, and Longfellow, and Whittier, and Holmes, are beautifully related each to each in a fatal rack-and-pinion combination. There is an implied causal connection, and everything is so perfectly adjusted that you begin to infer that nature amuses herself by playing an unending ball-and-socket game.

If you allow your mind a little freedom, however, or even indulge in a little common sense—that most uncommon and little valued of human attributes—you must perceive that the causal relationship among those American authors was purely imaginary. Emerson might have flourished and have been the complete Emerson whom we know, although Holmes and Hawthorne had never existed; and so not one of them was important, much less indispensable, to the development of the others. I do not mean, of course, that being contemporaries and acquaintances they had no superficial influences on each other, but I do mean that they were structurally independent.

Now to write literary history in this fashion is to falsify. The persons who produce it mean no harm; they are simply the unconscious victims of the instinct for process and of the instinct for precision; having only half learned the theory of evolution, they inevitably misuse it. Six or eight authors of a given generation loom up before them; what can be more certain than that these authors have some occult evolutionary interdependence?

Thus do personalities, the most fluid and elusive of essences, become petrified and standardized and made to fit into one another, and into the pattern which the historian has devised, as if they were pieces of metal, moulded into interlocking parts of a soulless machine.

The same calamity befalls a national history, or any episode in it, in the hands of historians of this sort. They, too, must account for everything, and carefully dovetail one incident into another, leaving no gap, for fear they may be thought undiligent, or inaccurate. So we have from them a perfectly consecutive story without breach or suture, the product, though the writers know it not, of our common craving for certitude. No class of our historical writers seems more prone to this defect than do the documentarians—by whom I mean those who devote themselves almost entirely to the inspection of documents, which they come sometimes to worship as fetishes. They withdraw themselves so far from actual life that they fail to understand that the written document alone is not the sole material of history, nor is it always the best.

The historian comes to his work with many prepossessions which must, if he gives them free play, lead him to strange and unexpected results. It is as if some demon urged him not to use his own eyes but to wear colored glasses; and as the colors vary, so will his pictures. The prepossessions of race, of creed, of a political party, or of an economic school are all temptations which he must resist. A judicious reader will not, of course, be deceived by them; indeed they will often help him to know more intimately than he otherwise could the principles and the desires which sway the zealots of creed or party. The writer who strives to be neutral or parades his impartiality may often lead us farther from the truth than does the partizan whose very zeal discloses it.

But there are still larger prepossessions which I may call cosmic. These are based on your ultimate conception of the universe, on what you think life is, and on your duties and relations towards it. I need hardly say that as long as man was regarded not only as the central object for which the earth was created, but also as the very sum and crown of life in the visible universe, the historians in the bonds of these prepossessions made a very different story of man’s deeds than anybody would make now. The Jews, for instance, looked upon themselves as the Chosen People, and in the Old Testament they pieced together fact, tradition, myth, poetry, religious and civil laws, and even sanitary and hygienic ordinances so as to prove their assumption. The early chronicles of other peoples—of Egyptians and Assyrians, of Babylonians and Chinese—have similar features. Even the open-minded and keen-sighted Greeks did not escape from assigning to Hellas supreme importance: the gods of Hellas were to them indisputably the highest of all deities, just as they themselves, the Hellenes, were first among men.

When we read the works of the Jews or Greeks, or other ancient peoples, we must remember, therefore, that this conviction of primacy lay in the back of the mind of each of them. It came to be taken for granted; it ceased to be debated or discussed.

Substituting creeds for races, we find just such a prepossession in the case of Christians and Mohammedans, and later, when Christians became divided, between Protestants and Roman Catholics. There was always the primal assumption that one creed was orthodox and that the supporters of all the other creeds were heretics. Likewise, among races yours was civilized and all the others were barbarian.

In the nineteenth century, however, came the revelation, now generally accepted among intelligent peoples, that the earth is not the centre of the universe, and consequently man’s cosmic position has completely changed. His history, at least so far as it concerns ultimates, must be wholly revised. As we look out at the Milky Way on a clear frosty night, we no longer modestly assume that its millions of stars and all the other suns and constellations were created and are whirling forever on their immeasurable circuits for the benefit of us mere men. Not only the scale by which we measure has changed, but the degree and the purpose.

The modern key word for solving the enigma is evolution, development, growth, not special creation according to theological assertions and guesses. After trying this key in every lock during the past sixty or seventy years, we find, as it seems to me, that it has opened to us not the secret of life itself, but the process by which we and all other living things, and all forms of matter, live.

Inevitably, the study of history and its writing felt the change and felt it so imperiously that for the last half-century historical students and writers have sought deliberately to record the process of evolution in human affairs. No doubt, the formula helps us to advance a long way towards truth, and it supersedes all the fantastic and arbitrary formulas which men employed earlier. But the question for us now is, how far should we employ it? Shall we make it so paramount that it obtrudes? Should it not rather be like the skeleton in man and most vertebrate animals, which really determines their form and motions but is concealed beneath a covering of flesh? The turtle, to be sure, wears its skeleton on its outside, but the turtle is, after all, neither the highest nor the most beautiful kind of animal. And may we not be misled by employing too rigidly in the human field formulas which apply best to the domain of matter, to the field of chemistry, for example, or of physics, or of astronomy?

I have long had my doubts as to the accuracy or propriety of calling history a science. We investigate historical material in the same way that a chemist investigates his material, but we must not therefore assume that the two sorts of materials are identical, or that the employment of similar methods by historians and chemists makes history a science in the same sense that chemistry is one. In these matters we are apt to quarrel over the mere words, the names of things, rather than over the things themselves behind the words. But in general I feel that the less an historian has to do with science, the less he deliberately imitates and assumes scientific aims and conclusions, the better.

Recently, on re-reading Henry Adams’s A Letter to American Teachers of History,1 I was confirmed in my conviction. How many know that extraordinary Letter by our master ironist—and, may I not also say, our master historian? There are passages in it so cryptic and other parts in which the intricacies of physics and dynamics are treated with such a nimble raillery, that I am not sure that I wholly understand them. But Henry Adams’s main thesis is clear enough. He had come very early on the theory of evolution and on the Darwinian illustrations of it, and then his eager and inquisitive mind had turned from organic nature to the study of mathematical and physical laws. Before you can know an animal or a man thoroughly you must know the laws of gravity, embolism, and all the other processes which control his physical growth.

For a few decades the scientific world rested complacently on the new demonstration of the law of the conservation of energy. Now, according to Mr. Adams’s view, history written by anyone who understood this law should in some way embody it, just as history written about the Saracens should reveal the Mohammedan creed, which formed the background of their life and actions. The revelation would not necessarily be formal or definite or vivid, but you would always be able to infer what it was that made the Saracens unlike other races.

Chronos, however, still devours his children as voraciously as he did when the old Greek myth-maker first caught him at this cannibalistic work. Hardly was the great law of the conservation of energy accepted as final, before William Thomson, better known to posterity as Lord Kelvin, flung into the scientific world his law of the dissipation of mechanical energy, which had been, in fact, propounded as early as 1824 by Carnot. According to Kelvin’s later definitive statement his law was as follows:

  1. There is at present in the material world a universal tendency to the dissipation of mechanical energy.
  2. Any restoration of mechanical energy, without more than an equivalent of dissipation, is impossible in inanimate material processes, and is probably never effected by means of organized matter, either endowed with vegetable life or subjected to the will of an animated creature.
  3. Within a finite period of time past, the earth must have been, and within a finite period of time to come, the earth must again be, unfit for the habitation of man as at present constituted, unless operations have been, or are to be performed, which are impossible under the laws to which the known operations going on at present in the material world are subject.

Mr. Adams devotes two hundred pages to a keen and often dazzling examination of this law, and of the stupendous deductions to be drawn from it. We need not follow him in the details. He may or may not be right in such a matter as suggesting that all fossil traces of the missing link which connected man with his simian forerunners have been buried beneath the polar ice-cap which gradually covered the earthly paradise existing round the North Pole before the Glacial Period. The upshot of his wit and analysis and argument and suggestion is destructive; for he implies that while the theory of evolution on its pleasant side pointed to the upward progress of humanity, it registered on its ruthless side the fated extinction of individuals.

How does all this affect the historian? First of all, Henry Adams would have the historian wisely instructed in the foundations of science, almost to such a degree that he might with a little extra study qualify as a teacher of physics. Next, the historian, being saturated with Kelvin’s law of the dissipation of energy, would so construct his history as to make it appear as an illustration of the working of that law. If I understand him, an adequate history of the Peloponnesian War or of the American Revolution would disclose how each was an experiment, so to speak, not merely in politics and war, but also in the dissipation of energy. There would be obvious difficulties in the way. What means of measuring this dissipation would the historian have? If Kelvin’s law is true, there must have been less energy in 1865, when our Civil War ended, than in 1861, when it began. The energy dissipated during these four years was not only human but material, solar, sidereal, cosmic. Who can compute it?

And, after all, why should we inject into our description of human affairs the law of dissipation rather than the law of gravitation, or of capillary attraction, or the binomial theorem? So far as any of these scientific truths, or any other, affected the conduct of men we may notice them, but not otherwise. The discoveries of Copernicus and the laws framed by Kepler, when they affected religion and theology and led to the efforts of hierarchs to persecute those persons who believed them, were as humanly pertinent as was any of the dogmas which caused religious wars. But in general, scientific facts, theories, and doctrines, should be reserved for the histories of science.

So far as Henry Adams reaches a conclusion, I may sum it up in his own words:

If the entire universe, in every variety of active energy, organic and inorganic, human or divine, is to be treated as clock-work that is running down, society can hardly go on ignoring the fact forever. Hitherto it has often happened that two systems of education, like the Scholastic and Baconian, could exist side by side for centuries … by no more scientific device than that of the shutting their eyes to each other; but the universe has been terribly narrowed by thermodynamics. Already History and Sociology gasp for breath.

The department of History needs to concert with the departments of biology, sociology, and psychology some common formula or figure to serve their students as a working model for the study of the vital energies; and this figure must be brought into accord with the figures or formulas used by the departments of physics and mechanics to serve their students as models for the working of physico-chemical and mechanical energies. Without the adhesion of physicists, the model would cause greater scandal than though the contradictions were silently ignored as now; but the biologists—or, at least, the branches of science concerned with humanity—will find great difficulty in agreeing on any formula which does not require from physics the abandonment, in part, of the second law of thermodynamics. The mere formal exception of Reason from the express operation of the law, as a matter of teaching in the workshop, is not enough. Either the law must be abandoned in respect to Vital Energy altogether, or Vital Energy must abandon Reason altogether as one of its forms, and return to the old dilemma of Descartes.

Here is science with a vengeance, enough one would suppose to satisfy the most zealous professor of scientific history, and much more than enough to tax the learning and wits of most of those who write and study any history. In reading Henry Adams’s astonishing tract, I cannot help suspecting at times that he is making fun of us historians; for he proposes, as I think you would agree with me, something which is not only impossible for anyone to carry out but which he himself never even attempted to carry out. In all the nine volumes of his American History, is there a hint of the second law of thermodynamics? Can you discover the slightest trace of a common formula for history and physical chemistry?

I find, on the contrary, Henry Adams’s annals of Jefferson and Madison packed full of human stuff. He is not content merely to mention a man by name; he draws that man’s portrait. ‘The interactions of persons, the rivalries of political parties, the intrigues of competing groups, the clashing of international diplomacy, are not described as examples of abstract laws, but as workings of the human will through concrete human beings. And how delicately and surely are his descriptions drawn! How admirably he probes the baffling complexes of character! And with what a wealth of allusion, borrowed equally from history and literature, he enriches his portraits and views! His reflections tinged with sarcasm, which springs now from his pessimism and now from his irony, complete this masterly specimen of historical writing.

In other words, Henry Adams refutes by his practice the theories which he professed. He was in the prime of life, in the years round fifty, when he wrote the History. He was twenty years older when he wrote the Letter to Teachers of History. Some men grow more abstract as they grow old; their interest in persons gives way to a greater interest in laws. I do not say that this was the case with Mr. Adams. Certainly, his Mont St. Michel and Chartres and his Education, written when he was sixty and over, have no mathematical chill and no thermodynamical abstractions about them.2 But he was a man possessed from youth to age with a passion for knowing the ultimate truth. Not having found that in religion, he turned to science, and when science, through Lord Kelvin, revealed to him the law of the dissipation of energy, he believed that in that law he touched ultimate truth. And so he exerted himself to trace the operation of that law in organic nature, including man, not less than in the inorganic world.

Your own view of life and human destiny must be greatly affected if, instead of believing in the upward progress of mankind as it develops on the earth and in its limitless perfectibility in other worlds, you interpret Kelvin’s law as Henry Adams did; that is, if you regard the energy of the universe as a clock that is slowly running down with the certainty that after millions, or it may be billions, of years its last ounce of power will be dissipated and there will be absolutely nothing left. The prospect does not cheer; and yet I submit that even the historian who holds this view has no more business to mix it up with the history he writes, than the painter who believes in annihilation has to let that belief interfere with the portrait he is painting of a beautiful woman.

No matter what a man does, he will doubtless reveal himself in ways he little suspects; I insist, however, that the historian should no more convert his history of a period or episode in the life of a people into a proof of Kelvin’s law of thermodynamics than into a disproof of quadratic equations. The time may come when human affairs may be described no longer by words and sentences, but by a system of symbols or notation similar to those used in algebra and chemistry. Then it may be possible, as Mr. Adams suggests, to invent a common formula for thermodynamics and history. I once had sent to me by a stranger a conclusive demonstration, which I could not refute, in the form of a combination of trapezoids, polygons, and parallelopipedons, of the doctrine of the Trinity. Perhaps I ought to add that the man was crazy; but his diagram taught me never to assert that anything is impossible.

You may say that no sensible man would attempt to write history as a demonstration of Kelvin’s law of dissipation; and yet you may insist that history is, nevertheless, a science and should be written as a science. You may, for instance, have been fascinated by that remarkable philosophic guesser, Giovanni Battista Vico, whose fertile and luminous suggestions lighted up a murky age as a shower of meteorites lights up a November evening. Convinced that his law of cycles in human development is well founded, you may wish to show this by your treatment of some historical theme. How will you do this? Where will you find the inevitable sequence of events which alone could make your proof scientific? What right have you to assume that progress is a regular moving forward? How do you know that it may not be an advance like that of the knight in chess? Is Vico’s series of cycles, which so captivate the imagination, more than a glorified metaphor? Is it really more scientific than the old, old simile that this life is like the chrysalis, and that death is the happy liberation of the imprisoned butterfly into another ampler life?

But why should we seek farther for evidence of the danger of trying to fit history to any theory when we, and the whole world, have been struggling to break loose from the coils of a misinterpreted phrase? I do not believe that the atrocious war into which the Germans plunged Europe in August, 1914, and which has subsequently involved all lands and all peoples, would ever have been fought, or at least would have attained its actual gigantic proportions, had the Germans not been made mad by the theory of the survival of the fittest. The Germans are the most amazing doctrinaires the world has ever seen; they are also the greatest pedants. Whatever subject attracts their attention, obsesses them; and to be obsessed means to lose contact with the normal measures and perspectives of life.

So the phrase, “the survival of the fittest”, obsessed them. Studying only the animal kingdom, they concluded that fitness was won by and depended upon brute force. The species possessing the greatest amount of force was, therefore, the fittest. Any of us, though we be not naturalists, can see how untrue this conclusion is, even when applied to the animal world. Frail creatures survive in spite of all the efforts of the strong creatures which prey upon them; and some of the frail have a far longer geologic ancestry than has the lion or the elephant. Insect tribes which flit hither and thither at the will of a passing breeze, date back aeons on aeons to conditions when no mammal trod the earth. If brute force alone were the test of fitness to survive, how could this be?

But we see, of course, that the vital consideration is, what do you mean by fitness? The fishes have a certain fitness which enables them to swim and to live under water; snakes have another by which they glide; insects and birds are fitted to fly; animals and man to walk and run. If you examine all these creatures, on the physical side alone, you find that something besides strength, physical force, has accounted for their being able to adjust themselves to their environment. Now, when we discover that at a certain point in mankind’s evolution moral considerations come in, we see that as the race develops morals play a more and more important part in determining fitness to survive. The higher races, like the higher individual types, cease to regard the possession of power—brute power, enabling them to kill or enslave their neighbors—as their final aim. In a family the brothers who are physically stronger do not beat their weaker sisters; in society, we do not allow the brawny man of six feet two, merely because he is big, to persecute or destroy the little man of five feet. Civilization lives by ideals, by standards with which the girth of a man’s chest or the thrust of his thighs has nothing to do.

The Germans, however, in their obsession, left all this out. Hindenburg, colossal in form and brutish in nature, could knock down, trample, and destroy Goethe, shall we say that he thereby could prove that he was fitter than Goethe to survive? At any rate, in the imaginary conflict, he survived, and Goethe didn’t.

This obsession it is which underlies the German ambition to rule the world. Being a very conceited and a very envious people, the Germans were easily led by their masters into believing that they were the fittest of all peoples to survive. Their men of science assured them that biology established that, and they were too devout materialists to question a supposed biological law, especially one which so flattered themselves. To convert them through education and military training into a warlike people, to persuade them that war is the highest duty, the noblest pursuit of man, to poison their conscience by teaching them that in war neither morals nor humanity have any place, these were easy tasks for the ambitious Prussian war-lords and their docile servants. Thus, we see the damnation into which those are led who misinterpret a phrase, or a law, if you will, and would make history and biology their accomplices in the most frightful crimes ever committed against laws human and divine.

Let us rather strive to redeem history from the bonds of scientific formulas, and of scientific purposes. Let us strive to humanize it. In so doing, the historian will abdicate no high and hard-won office; on the contrary, he will rise to the full glory of his mission. If he must have some watchword to guide him, let that watchword be “Man the Measure”—man, not the laws which apply to the animal kingdom, or to unthinking and soulless matter. Human nature is the substance in which the historian must work. He must try to discover how the human will—that force more mysterious than electricity—shapes and directs the deeds of men. These deeds it is which make up the web of history. In this web, one deed leads to and determines the next, one event succeeds another in what seems to be a fated chain of cause and effect.

May we not say that there are three classes of historians? First, those who fix their attention on externals, that is, on deeds and events which are visible to everyone; next, those who search for the inner motive, the operation of the will behind the outward acts; and finally, those who, through their description of the outer, interpret the inner causes. I do not mean to imply that an historian deliberately, or even consciously, enrolls himself in one or another of these classes. His case is like that of a painter who expresses his temperament through color or through line according to his native talent. Of course, I would not imply that the division between one class of historian and another is always rigid; on the contrary, the classes often overlap.

As every historical student who has done more than scrape the surface of his subject knows, he encounters his chief difficulty when he deals with motives. It is easy enough to epitomize or paraphrase a file of consecutive documents; the real task is to search out the motives which gave rise to them. These are often unrecorded, or elusive, needing to be deduced or divined by some special instinct in the historian. This power of divination distinguishes the physician who is a master in diagnosis from his fellows who may be even more learned than he, but who lack it; this truth applies to historians also.

Those who regard history as the manifestation of will reap the richest compensation in its study. The very uncertainty of its operations, the gaps in the evidence, the impasses, the contradictions which need to be adjusted, keep the mind continually on the alert, and tease the wits to discover a solution. When we deal with history in the mass, over long periods of time, we are less likely to discern manifestations of will. Multitudes seem to move by a collective momentum, as a flood does, without foresight or choice, at the mercy of brute, material laws. Only when we come to that stage in human development where individuals emerge from the vast indistinct masses and lead them, or at least visibly influence them, does will confront us. This is what makes the history of Athens so much more significant and interesting than that of ancient. Assyria or of Egypt; this is what gives modern and contemporary history, abounding in many well-defined individuals, its absorbing attraction for us; this is what makes biography the crowning flower of history, as portraiture is of painting.

Even if we were able to search the hearts of men to the bottom, and to know all their motives, there would still remain what we call chance, or fortune, to disconcert and puzzle us. Sometimes we can see plainly enough from what quarter the stroke of chance comes, but we never can foresee it, and it is this inability of the historian to foresee which differentiates him from the students of exact science. The Athenian general, Nicias, refused to withdraw his army from Syracuse at a time when it might have been saved. His reason was that an eclipse occurred, and he regarded this as a bad omen. If the Greeks had known more astronomy, they could have predicted the eclipse; further, the Athenians might well have known how Nicias was influenced by such portents, so that there was really no chance in the affair; but at the time it seemed as if the Athenians were the sport of unpredictable fortune. If President Wilson, or Mr. Lloyd George, were to die to-night, the course of world events would inevitably be deflected, but in what direction, or how far, we cannot foresee. Thus, the caprices of fortune, added to the difficulty of fathoming human motives, increase the labors and pique the zest of the historian.

It may be that Sesostris was as great an individual as Napoleon, and that his conquests and government were as significant as Napoleon’s; but we shall never believe it because we shall never know about Rameses the Second a thousandth part of what we know about Napoleon. I am aware that among some historical students today who regard history as the interaction of impersonal, abstract laws, Napoleon is looked upon as a “negligible quantity”, but I am unskilled in using either the telescope or the microscope when it comes to examining human deeds and motives. A man’s eyes are the only proper instrument for scrutinizing men. Not merely Napoleon, but mankind, and our earth itself, must seem negligible, if their existence is known at all to the other denizens of the sidereal wilderness; but the historian has no more to do with the limitless perspectives of astronomy than with the elusive intricacies of thermodynamics.

Let me repeat that “Man the Measure” should be the guiding motto for those who would write history in human terms.

We historians have the noblest of callings. Unlike the dramatist or the epic poet, we do not invent our plot nor create the characters in the play. The Creator of all things supplies these. It is for us to discern them accurately, to describe them with all the truth there is in us, and to make them live again; for life is the one indispensable God-given essence, and it must throb through our copies as it did through their models. Years ago, Bonnat, the French painter, was making a portrait of an American, and he came so unpleasantly close and looked so hard and intently that the American drew back and asked what it meant. “Good heavens!” replied Bonnat, “I am competing with God, and I must see everything which He has put into your face.”

We historians also compete with God, and we must leave nothing undone to make our poor transcripts of His masterpieces true to the divine originals.

William Roscoe Thayer (1859–1923) received a master’s degree at Harvard University in 1886. He was best known for his works on Italian history, especially The Dawn of Italian Independence 1814 to 1840, 2 vols. (1893); A Short History of Venice (1905), and The Life and Times of Cavour, 2 vols. (1911).



  1. Privately printed in 1910. []
  2. To be strictly accurate, Henry Adams, in the final chapters of the Education, refers to his excursions into science; but these chapters are hardly read with the most profit or remembered with the most pleasure. []