Greg+Silva+-+Week+2

While I admire the efforts of such scientist/philosophers as Aristotle and Ptolemy to understand the world around them, their lack of observational tools seriously crippled their efforts.

One of the most glaring cases of this problem was in the Ptolemaic version of the Solar System. Ptolemy, like many Greeks before him, had "no notion of inertia, [and] could hardly deal effectively within the framework of a moving-earth system" (Hatch). This total lack of knowledge of inertia, compounded with the concept of a four-element system (consisting of earth, water, air, and fire) derived from a lack of chemical testing and knowledge, led ancient Greek scientists such as Aristotle to conclude that inanimate objects fall to the earth because "elements tend to seek their natural place in the order of things" (Fowler). Since many of these objects, in Aristotle's mind and Ptolemy's as well, contained and abundance of earth, they fell. Extending this idea, the Earth itself, being made entirely of earth, must have held the lowest position possible, in the center of the universe.

Further, classical Greek scientists, convinced that the heavens were perfect and unchanging, insisted that "heavenly bodies were not made up of the four elements earth, water, air and fire, but of a fifth, different, element called aither, whose natural motion was circular" (Fowler). Ptolemy used a system of deferents and epicycles to explain, accurately by the measurements availible to the ancient Greeks, planetary motion. Until telescopes existed that could take more accurate observations and Johannes Kepler, with Tycho Brahe's enormous collection of astronomical data, hypothesized that planets move in ellipses, the Ptolemaic system stood more or less unquestioned.

Similarly, the lack of knowledge in the field of physics crippled early efforts at understanding the universe. Because "Aristotle believed the velocity of any object in motion was contingent on the force of propulsion as well as the resistance of the medium traversed" (Hatch), not only inertia but also the concept of a void were not possible for ancient Greeks; in a world where V = F/R, R can never be 0! Since ancient Greeks had no means of creating anything resembling a void, nor a way to counteract friction enough to observe nearly frictionless motion, even anyone who believed in other views could not have generated sufficient evidence to suggest that their idea was more valid than Aristotle's.