About Saint Thomas's theology we need not greatly disturb ourselves; it can matter now not much, whether he put more pantheism than the law allowed or more materialism than Duns Scotus approved—or less of either—into his universe, since the Church is still on the spot, responsible for its own doctrines; but his architecture is another matter. So scientific and structural a method was never an accident or the property of a single mind even with Aristotle to prompt it. Neither his Church nor the architect's church was a sketch, but a completely studied structure. Every relation of parts, every disturbance of equilibrium, every detail of construction was treated with infinite labour, as the result of two hundred years of experiment and discussion among thousands of men whose minds and whose instincts were acute, and who discussed little else. Science and art were one. Thomas Aquinas would probably have built a better cathedral at Beauvais than the actual architect who planned it; but it is quite likely that the architect might have saved Thomas some of his errors, as pointed out by the Councils of 1276. Both were great artists; perhaps in their professions, the greatest that ever lived; and both must have been great students beyond their practice. Both were subject to constant criticism from men and bodies of men whose minds were as acute and whose learning was as great as their own. If the Archbishop of Canterbury and the Bishop of Paris condemned Thomas, the Bernardines had, for near two hundred years, condemned Beauvais in advance. Both the "Summa Theologiae" and Beauvais Cathedral were excessively modern, scientific, and technical, marking the extreme points reached by Europe on the lines of scholastic science. This is all we need to know. If we like, we can go on to study, inch by inch, the slow decline of the art. The essence of it—the despotic central idea—was that of organic unity both in the thought and the building. From that time, the universe has steadily become more complex and less reducible to a central control. With as much obstinacy as though it were human, it has insisted on expanding its parts; with as much elusiveness as though it were feminine, it has evaded the attempt to impose on it a single will. Modern science, like modern art, tends, in practice, to drop the dogma of organic unity. Some of the mediaeval habit of mind survives, but even that is said to be yielding before the daily evidence of increasing and extending complexity. The fault, then, was not in man, if he no longer looked at science or art as an organic whole or as the expression of unity. Unity turned itself into complexity, multiplicity, variety, and even contradiction. All experience, human and divine, assured man in the thirteenth century that the lines of the universe converged. How was he to know that these lines ran in every conceivable and inconceivable direction, and that at least half of them seemed to diverge from any imaginable centre of unity! Dimly conscious that his Trinity required in logic a fourth dimension, how was the schoolman to supply it, when even the mathematician of to-day can only infer its necessity? Naturally man tended to lose his sense of scale and relation. A straight line, or a combination of straight lines, may have still a sort of artistic unity, but what can be done in art with a series of negative symbols? Even if the negative were continuous, the artist might express at least a negation; but supposing that Omar's kinetic analogy of the ball and the players turned out to be a scientific formula!—supposing that the highest scientific authority, in order to obtain any unity at all, had to resort to the Middle Ages for an imaginary demon to sort his atoms!—how could art deal with such problems, and what wonder that art lost unity with philosophy and science! Art had to be confused in order to express confusion; but perhaps it was truest, so.
Some future summer, when you are older, and when I have left, like Omar, only the empty glass of my scholasticism for you to turn down, you can amuse yourselves by going on with the story after the death of Saint Louis, Saint Thomas, and William of Lorris, and after the failure of Beauvais. The pathetic interest of the drama deepens with every new expression, but at least you can learn from it that your parents in the nineteenth century were not to blame for losing the sense of unity in art. As early as the fourteenth century, signs of unsteadiness appeared, and, before the eighteenth century, unity became only a reminiscence. The old habit of centralizing a strain at one point, and then dividing and subdividing it, and distributing it on visible lines of support to a visible foundation, disappeared in architecture soon after 1500, but lingered in theology two centuries longer, and even, in very old-fashioned communities, far down to our own time; but its values were forgotten, and it survived chiefly as a stock jest against the clergy. The passage between the two epochs is as beautiful as the Slave of Michael Angelo; but, to feel its beauty, you should see it from above, as it came from its radiant source. Truth, indeed, may not exist; science avers it to be only a relation; but what men took for truth stares one everywhere in the eye and begs for sympathy. The architects of the twelfth and thirteenth centuries took the Church and the universe for truths, and tried to express them in a structure which should be final. Knowing by an enormous experience precisely where the strains were to come, they enlarged their scale to the utmost point of material endurance, lightening the load and distributing the burden until the gutters and gargoyles that seem mere ornament, and the grotesques that seem rude absurdities, all do work either for the arch or for the eye; and every inch of material, up and down, from crypt to vault, from man to God, from the universe to the atom, had its task, giving support where support was needed, or weight where concentration was felt, but always with the condition of showing conspicuously to the eye the great lines which led to unity and the curves which controlled divergence; so that, from the cross on the fleche and the keystone of the vault, down through the ribbed nervures, the columns, the windows, to the foundation of the flying buttresses far beyond the walls, one idea controlled every line; and this is true of Saint Thomas's Church as it is of Amiens Cathedral. The method was the same for both, and the result was an art marked by singular unity, which endured and served its purpose until man changed his attitude toward the universe. The trouble was not in the art or the method or the structure, but in the universe itself which presented different aspects as man moved. Granted a Church, Saint Thomas's Church was the most expressive that man has made, and the great Gothic cathedrals were its most complete expression.
Perhaps the best proof of it is their apparent instability. Of all the elaborate symbolism which has been suggested for the Gothic cathedral, the most vital and most perfect may be that the slender nervure, the springing motion of the broken arch, the leap downwards of the flying buttress,—the visible effort to throw off a visible strain,—never let us forget that Faith alone supports it, and that, if Faith fails, Heaven is lost. The equilibrium is visibly delicate beyond the line of safety; danger lurks in every stone. The peril of the heavy tower, of the restless vault, of the vagrant buttress; the uncertainty of logic, the inequalities of the syllogism, the irregularities of the mental mirror,—all these haunting nightmares of the Church are expressed as strongly by the Gothic cathedral as though it had been the cry of human suffering, and as no emotion had ever been expressed before or is likely to find expression again. The delight of its aspirations is flung up to the sky. The pathos of its self-distrust and anguish of doubt is buried in the earth as its last secret. You can read out of it whatever else pleases your youth and confidence; to me, this is all.