behavior, he argued against Descartes' dualistic view on the mind. His opinions were so strong that he stated that Descartes was actually a materialist in regards to the mind. The philosopher David Skrbina considers La Mettrie an adherent of "vitalistic materialism": Man and the animal Prior to Man a Machine he published The Natural History of the Soul in 1745. He argued that humans were just complex animals. A great deal of controversy emerged due to his belief that "from animals to man there is no abrupt transition". He later built on that idea: he claimed that humans and animals were composed of organized matter. He believed that humans and animals were only different in regards to the complexity that matter was organized. He compared the differences between man and animal to those of high quality pendulum clocks and watches stating: "[Man] is to the ape, and to the most intelligent animals, as the planetary pendulum of Huygens is to a watch of Julien Le Roy". The idea that essentially no real difference between humans and animals existed was based on his findings that sensory feelings were present in animals and plants. While he did recognize that only humans spoke a language, he thought that animals were capable of learning a language. He used apes as an example, stating that if they were trained they would be "perfect [men]". He further expressed his ideas that man was not very different from animals by suggesting that we learn through imitation as do animals. His beliefs about humans and animals were based on two types of continuity. The first being weak continuity, suggesting that humans and animals are made of the same things but are organized differently. His main emphasis however was on strong continuity, the idea that the psychology and behavior between humans and animals was not all that different. Man a machine La Mettrie believed that man worked like a machine due to mental thoughts depending on bodily actions. He then argued that the organization of matter at a high and complex level resulted in human thought. He did not believe in the existence of God. He rather chose to argue that the organization of humans was done to provide the best use of complex matter as possible. La Mettrie arrived at this belief after finding that his bodily and mental illnesses were associated with each other. After gathering enough