After the brilliant triple star Socrates-Plato-Aristotle was extinguished, the philosophical sky was covered with dark clouds. The heathens stepped from the stage, and Christianity and the dogmas of its church predominated the logic of men, until at last a new scientific light arose in the beginning of modern times. It was especially Cartesius and Spinoza who were most brilliant among the early thinkers that emancipated their minds slowly and under great difficulties. Spinoza, of Jewish descent, is especially interesting in his fight against narrowmindedness and for a universal philosophy. He wrote an "Essay on the Improvement of the Intellect and on the Way by which it is best led to a true Understanding of Things." He, as well as we, was looking for the best way, the true way, the way of truth. He, as well as we, seeks to study and practice the fundamentals of the art of thought. He begins: "After experience has taught me that everything which the ordinary life offers is vain, and I have seen that everything which I feared is only good or bad in so far as the mind is moved by it, I finally resolved to investigate whether there is any true good--whether there is anything the discovery of which will forever secure continuous and supreme joy. What is most generally found in life, and what mankind regards as the highest good, may be reduced to three things, viz., wealth, honor, and sensual pleasure." After Spinoza has then uncovered the shadowy side and the vanity of these popular ideals, he calls them "unsafe by their very nature," while he is looking for "permanent good," which is "insecure only as regards its possession, but not in its nature." But how is that to be found? "Here I shall say shortly what I mean by true good, and what is at the same time the highest good. In order to grasp this fully, we must remember that good or bad are only relative terms, and thus the same thing may be called good or bad according to its relations, or on the other hand perfect or imperfect." Spinoza, forestalling the object of his research, discovers that the true, supreme and permanent good is the "understanding of the unity" of the soul with the entire nature. "This then," he says, "is the goal which I am coveting." "To this end, we must study morals, philosophy, and the education of boys, and combine with this study the entire science of medicine, because health materially assists us in reaching our ideal. Neither must mechanics be neglected, because many difficult things are made easy by art. Above all we must strive to find a way for the improvement of the intellect."