 What ultimately sets apart humans from animals is the knowledge of God and morals. In the middle of the Treatise of Animals, Condillac inserts a long chapter he claims to have submitted as an anonymous dissertation to the Academy of Berlin just a few years before. Here Condillac proceeds to demonstrate the existence of God. Condillac insists on a natural progression of ideas: at first, humans realized that their happiness or unhappiness depended completely on external causes and posited deities equivalent to the powers of nature. Then they came to posit a first cause in order to avoid an infinite regression in explanation of these natural powers. Finally, the presence of design leads them to recognize this cause as intelligent and free (Treatise of Animals II.6). While the details of this chapter are not original, they set the stage for Condillac’s moral argument for the immortality of the soul.