In this book, the author presents 15 essays in which expresses his opinion on major issues as philosophy of science, economics and mathematics; scientific progress and moral regression; relativity, space and time; the facts that most have influenced to change the philosophical thought; effect of atom in economic and social behavior of human groups; impact of rationalist ideas on the economy; spirit and soul; sources of knowledge; the relativity of mathematical exactitude; why the infinitesimal calculus is limited and the equation of the harmony of the universe, concepts and ideas that...