§ 1. The beginning of the 17th century brought with it a change in the main direction of thought and interest. As we have seen, the 16th century adored literature and was thrown back on the remote past. Some of the great scholars like Sturm had indeed visions of literary works to be written, that would rival the old models on which they were fashioned; but whether they hoped or not to bring back the Golden Age all the scholars of the Renascence thought of it as _having been_. With the change of century, however, a new conception came into men’s minds. Might not this worship of the old writers after all be somewhat of a superstition? The languages in which they wrote were beautiful languages, no doubt, but they were ill adapted to express the ideas and wants of the modern world. As for the substance of these old writings, this did not satisfy the cravings of men’s minds. It left unsolved all the main problems of existence, and offered for knowledge mere speculations or poetic fancies or polished rhetoric. Man needed to understand his position with regard to God and to Nature; but on both of these topics the classics were either silent or misleading. Revelation had supplied what the classics could not give concerning man’s relation to God; but nothing had as yet thrown light on his relation to Nature. And yet with his material body and animal life he could not but see how close that relation was, and could not but wish that something about it might be _known_, not simply guessed or feigned. Hence the demand for _real_ knowledge, that is, a knowledge of the facts of the universe as distinct from the knowledge of what men have thought and said. We have heard of the mathematician who put down Paradise Lost with the remark that it seemed to him a poor book, for it did not prove anything; and it was just in this spirit that the new school of thinkers, the Realists, looked upon the classics. They wanted to know Nature’s laws: and words which did not convey such knowledge seemed to them of little value. § 2. Here was a tremendous revolution from the mode of thought prevalent in the Renascence. No longer was the Golden Age in the past. In science the Golden Age must always be in the future. Scientific men start with what has been discovered and add to it. Every discovery passes into the common stock of knowledge, and becomes the property of everyone who knows it just as much as of the discoverer. Harvey had no more property in the circulation of the blood, Newton and Leibnitz no more property in the Differential Calculus than Columbus in the Continent of America; indeed not so much, for Columbus gained some exclusive rights in America, but Harvey gained none over the blood.