Aristotle is considered the world's first scientist and the greatest of all natural philosophers. We can summarize his theories in four pillars: 1. Nature tends toward an end, from a state of potency to a state of act, that is, the embodiment of form in matter. 2. Aristotle assumes that the earth is spherical and that it is at the center of the Universe in a state of rest; which is surrounded by concentric and spherical layers of water, air and fire or the warm; and above these are the celestial spheres, being the superior of them, which is that of the fixed stars, which owes its movement to the First Motor. 3. He defines Nature as the set of all material things capable of changing and developing with a specific purpose. All movement towards change is produced by an external agent that puts into action the intrinsic tendency of natural objects to change 4. Aristotle proposes a theory of the temporal evolution of the beings, being the inorganic matter in the lower part of the scale and in the superior the organized matter, considering the plants inferior to the animals.
