Aristotle taught logic to Alexander the Great and, through his philosophical work, to every philosopher after him and up to our days. In this classic book, American philosopher Mortimer J. Adler teaches us all the essence of the uncommon sense of Aristotelian logic, presenting Aristotelian cosmology and philosophy in a contemporary, enjoyable, and clear way. By bringing Aristotelian work into everyday life, encouraging readers to think philosophically, this book opens up a unique path of cultivating thinking and critical ability, self-awareness, and self-realization.