Economics is closely related to the other social sciences, particularly politics, sociology (because some academics argue that economics is in fact a branch of sociology) and ethics; there are also strong connections with psychology, as economics is often influenced and affected by human behavior patterns. Economic thought dates back to ancient Athens with Plato and Aristotle both describing fledgling economic models in their writings.
Sociology, which is the study of human social behavior, can have a quantifiable effect on the application of economics in many ways. Stock market prices, for example, are often influenced much more by the perceptions of investors and shareholders than by actual hard data. Understanding what drives human behavior can lead to a better prepared economic model, and can also mean markets can be tailored around specific patterns of behavior.
Politics and economics are more visibly connected, thanks to the inseparable link between the science of state and the health of the economy. Interestingly, there is much debate about the level of agreement academic economists have with political economic decisions, due to the often long time scales needed to effect and alter economic models, which is often at odds with the need for quick political fixes.