Conatus'tan kuvvete Leibniz fiziği = Physics of Leibniz from the Conatus to the force

In this study is treated the process driving Leibniz to found the dynamics as the science of the force and it consists of two parts, each related to his ideas on the physics, prior and posterior to his use of the concept of the force. In the first part is focused the period of his youth until he discovered the principle of the equivalence of cause and effect in 1676. This period is marked with two different perspectives on the physics. In the first perspective, by rejecting completely the substantial forms as active principles in the body itself the young Leibniz considers, first of all, the nature of the body consists of the extension and the impenetrability alone, and sees the God as the only efficient and final cause of the universe. According the second perspective, developed by him in 1671, based on theories of concrete and abstract movements, the body has its own principle of action as the source of its own movement. That?s why Leibniz would claim now that the nature of the body consists of movement rather than of extension. Furthermore, since the body has its own principle of action, God doesn?t have to interfere no longer to the universe perpetually. In the second part of our study, is treated the concept of force, which is introduced into the philosophy of Leibniz with the discovery of the principle of the equivalence of cause and effect in 1676, and related to that, the process which drove him to recognize the substantial forms as active principles in the bodies. Keywords : Motion, Force, Quantity of motion, Conatus, Mens, Substantial Form