branches were derived from a common stock, has persisted without interruption in spite of many adversities and revolutions, and has displayed in successive generations the progress of general civilization, and the goal which man is able to reach in his highest perfection of mind and body, favoured by the physical and biological conditions of climate.  In this race, whether with respect to myth and science or to civilization, the theory of evolution has practically been carried out in all its phases and degrees.

Science and freedom were the great factors of civilization, or of progress in every kind of conceptions, sentiments, and social conditions:  the first dissolved and destroyed the matrix of myth in which the intelligence was at first enveloped, and liberty, which was wholly due to science, made steady progress a matter of certainty.  So that it may be said that the whole web of human history, so far as it consists in civilization or the progress of all good things, of the arts, and of every intellectual and material achievement, was the conflict of science, and her offspring freedom, against ignorance, and the despotism which results from ignorance, under all the social forms in which they are manifested.  So that all good and wise men, sincere lovers of the dignity of mankind and of the welfare of society and of the individual, ought to feel a deep reverence and love for these two powers, and to be ready to give up their lives to them.  For if—­which in the present condition of the world is an impossible hypothesis—­they were to fail, the human race would be irretrievably lost, since these are our real liberators from barbarism, which have upheld mankind in the struggle against it, under whatever name these principles have appeared.

I am aware that my theory will meet with many obstinate and zealous opponents in Italy, since I use the simple terms of reason and science, unqualified by other arguments, and I maintain the absolute independence of free thought.  Opposition is the more likely since science and freedom have been held responsible for sectarian intemperance, for the disturbances of the lower orders, for the inevitable disasters, the social and intellectual aberrations both of the learned and of the common peoples:  science and freedom are held to have repeated the wiles of the serpent in Eden.  But I am not uneasy at the thought of such opposition, since the progress of the human race has been owing to the fact that men convinced of the truth took no heed of the superstitious and interested war waged against them, sometimes from ignorance of things in general and of the law which governs civilization, sometimes from honest conviction.