I revered our theology, but, since the way to heaven lies open to the ignorant no less than to the learned, and the revealed truths which lead thither are beyond our intelligence, I did not dare to submit them to my feeble reasonings.
In philosophy there is no truth which is not disputed, and which, consequently, is not doubtful; and,as to the other sciences, they all borrow their principles from philosophy.
Therefore, I entirely gave up the study of letters, and employed the rest of my youth in travelling, being resolved to seek no other science than that which I might find within myself, or in the Great Book of the World.
Here the best lesson that I learned was not to believe too firmly anything of which I had learnt merely by example and custom; and thus little by little was delivered from many errors which are liable to obscure the light of nature, and to diminish our capacity of hearing reason. Finally, I resolved one day to study myself in the same way, and in this it seems to me I succeeded much better than if I had never departed from either my country or my books.
II.--The Intellectual Crisis
Being in Germany, on my way to rejoin the army after the coronation of the Emperor [Ferdinand II.], I was lying at an inn where, in default of other conversation, I was at liberty to entertain my own thoughts. Of these, one of the first was that often there is less perfection in works which are composite than in those which issue from a single hand. Such was the case with buildings, cities, states; for a people which has made its laws from time to time to meet particular occasions will enjoy a less perfect polity than a people which from the beginning has observed the constitution of a far-sighted legislator. This is very certain, that the estate of true religion, which God alone has ordained, must be incomparably better guided than any other. And again, I considered that as, during our childhood, we had been governed by our appetites and our tutors, which are often at variance, which neither of them perhaps always gave us the bestcounsel, it is almost impossible that our judgments should be so pure and so solid as they would have been if we had had the perfect use of our reason from the time of our birth, and had never been guided by anything else.
Hence, as regarded the opinions that I had received into my belief, I thought that, as a private person may pull down his own house to build a finer, so I could not do better than remove them therefrom in order to replace them by sounder, or, after I should have adjusted them to the level of reason, to establish the same once more.
When I was younger I had studied logic, analytical geometry, and algebra. Of these, I found that logic served rather for explaining things we already know; while of geometry and algebra, the former is so tied to the consideration of figures that it cannot exercise the understanding without wearying the imagination, and the latter is so bound down to certain rules and ciphers that it has been made a confused and obscure art which hampers the mind instead of a science which cultivates it. And as a state is better governed which has but few laws, and those laws strictly observed, I believed that I should find sufficient four precepts which follow.
The first was never to accept anything as true when I did not recognise it clearly to be so--that is to say, carefully to avoid precipitation and prejudice, but to include in my opinions nothing beyond that which should present itself so clearly and distinctly to my mind that I might have no occasion to doubt it.
The second was to divide up the difficulties which I should examine into as many parts as possible, and as should be required for their better solution.