The world never saw a more complete system of dogmatic theology than that elaborated by Thomas Aquinas. When the knowledge of the Greek and Hebrew was rare and imperfect, and it was impossible to throw light by means of learning and science on the texts of Scripture, it was well to follow the interpretation of such a great light as Augustine, and assume his dogmas as certainties, since they could not then be controverted; and thus from them construct a system of belief which would confirm the faith. But Aquinas, with his Aristotelian method of syllogism and definitions, could not go beyond Augustine. Augustine was the fountain, and the water that flowed from it in ten thousand channels could not rise above the spring; and as everybody appealed to and believed in Saint Augustine, it was well to construct a system from him to confute the heretical, and which the heretical would respect. The scholastic philosophy which some ridicule, in spite of its puerilities and sophistries and syllogisms, preserved the theology of the Middle Ages, perhaps of the Fathers. It was a mighty bulwark of the faith which was then accepted. No honors could be conferred on its great architects that were deemed extravagant.
The Pope and the clergy saw in Thomas Aquinas the great defender of the Church,--not of its abuses, but of its doctrines. And if no new light can be shed on the Scripture text from which assumptions were made; if these assumptions cannot be assailed, if they are certitudes,--then we can scarcely have better text-books than those furnished to the theologians of the Middle Ages, for no modern dialetician can excel them in severity of logic. The great object of modern theologians should be to establish the authenticity and meaning of the Scripture texts on which their assumptions rest; and this can be done only by the method which Bacon laid down, which is virtually a collation and collection of facts,--that is, divine declarations. Establish the meaning of these without question, and we have principia from which we may deduce creeds and systems, the usefulness of which cannot be exaggerated, especially in an age of agnosticism. Having fundamental principles which cannot be gainsaid, we may philosophically draw deductions. Bacon did not make war on deduction, when its fundamental truths are established.
Deduction is as much a necessary part of philosophy as induction:
it is the peculiarity of the Scotch metaphysicians, who have ever deduced truths from those previously established. Deduction even enters into modern science as well as induction. When Cuvier deduced from a bone the form and habits of the mastodon; when Kepler deduced his great laws, all from the primary thought that there must be some numerical or geographical relation between the times, distances, and velocities of the revolving bodies of the solar system; when Newton deduced, as is said, the principle of gravitation from the fall of an apple; when Leverrier sought for a new planet from the perturbations of the heavenly bodies in their orbits,--we feel that deduction is as much a legitimate process as induction itself.
But deductive logic is the creation of Aristotle; and it was the authority of Aristotle that Bacon sought to subvert. The inductive process is also old, of which Bacon is called the father. How are these things to be reconciled and explained? Wherein and how did Bacon adapt his method to the discovery of truth, which was his principal aim,--that method which is the great cause of modern progress in science, the way to it being indicated by him pre-eminently?
The whole thing consists in this, that Bacon pointed out the right road to truth,--as a board where two roads meet or diverge indicates the one which is to be followed. He did not make a system, like Descartes or Spinoza or Newton: he showed the way to make it on sound principles. "He laid down a systematic analysis and arrangement of inductive evidence." The syllogism, the great instrument used by Aristotle and the Schoolmen, "is, from its very nature, incompetent to prove the ultimate premises from which it proceeds; and when the truth of these remains doubtful, we can place no confidence in the conclusions drawn from them." Hence, the first step in the reform of science is to review its ultimate principles; and the first condition of a scientific method is that it shall be competent to conduct such an inquiry; and this method is applicable, not to physical science merely, but to the whole realm of knowledge. This, of course, includes poetry, art, intellectual philosophy, and theology, as well as geology and chemistry.
And it is this breadth of inquiry--directed to subjective as well as objective knowledge--which made Bacon so great a benefactor.
The defect in Macaulay's criticism is that he makes Bacon interested in mere outward phenomena, or matters of practical utility,--a worldly utilitarian of whom Epicureans may be proud.
In reality he soared to the realm of Plato as well as of Aristotle.