He describes in detail the circulatory, lymphatic, respiratory, digestive, endocrine, nervous, and sensory systems in a wide variety of animals but explains that the presence of a soul makes each organism an indivisible whole.
Dia menjelaskan secara rinci peredaran darah, limfatik, pernafasan, pencernaan, endokrin, saraf, dan sistem sensorik dalam berbagai macam hewan, tetapi menjelaskan bahwa kehadiran jiwa membuat setiap organisme keseluruhan terpisahkan.