This book contains the first lectures given by Master Omraam Mikhael Aivanhov in 1938 in Paris, shortly after his arrival from Bulgaria. They already reveal the timeless truths that are at the core of this teaching, enabling everyone to shape their existence meaningfully. It wonderfully connects living spiritual knowledge with the reality that every person experiences in daily life. By demonstrating that the laws valid on a material level are also valid on a spiritual level, he brings the truth seeker closer to the magnificent unity of creation. Every science, whether it be biology, astronomy, chemistry, economics, etc., gains an unprecedented expansion when applied in the realm of the soul and spirit.