Erasmus 2017-2018 Inventors and innovators Thales of Miletus Thales of Miletus (624-546 BC) was a pre-Socratic Greek philosopher, mathematician, and astronomer from Miletus in Asia Minor. He was one of the Seven Sages of Greece. Many, most notably Aristotle, regarded him as the first philosopher in the Greek tradition and he is otherwise historically recognized as the first individual in Western civilization known to have entertained and engaged in scientific philosophy. Thales is recognized for breaking from the use of mythology to explain the world and the universe, and instead explaining natural objects and phenomena by theories and hypotheses, in a precursor to modern science. Aristotle reported Thales' hypothesis that the originating principle of nature and the nature of matter was a single material substance: water.
Mathematics In mathematics, Thales used geometry to calculate the heights of pyramids and the distance of ships from the shore. He is the first known individual to use deductive reasoning applied to geometry, by deriving four corollaries to Thales' theorem. He is the first known individual to whom a mathematical discovery has been attributed.
Intercept theorem The intercept theorem states that: “If two intersecting lines are cut by parallel lines, the line segments cut by the parallel lines from one of the lines are proportional to the corresponding line segments cut by them from the other line” (see figure 1).
Figure 1: Intercept theorem