Mathematics emerged in history around the same time as agriculture, and for the very practical reason that it was necessary to quantify crops and to count the days to determine planting and harvesting times. Since then, the need for mathematics and the range of its applications have grown enormously. This program looks at some of the theories and their applications: the probability theory, which enables us to calculate our chances of success in risky situations; and Euclidean geometry, which allows us to understand the relations between shapes and forms of objects, with countless applications in today’s world. A more recent advance is the theory of chaos, which addresses complex phenomena in nature, from the human heartbeat to the flow of a stream of water. (23 minutes)