Epicureanism, less commonly Epicurism, is a school of philosophy founded in 307 BCE and based upon the teachings of Epicurus, an ancient Greek philosopher. Epicurus was an atomist and materialist, following in the steps of Democritus. His materialism led him to religious skepticism and a general attack on superstition and divine intervention. Epicureanism was originally a challenge to Platonism, and its main opponent later became Stoicism. It is a form of hedonism insofar as it declares pleasure to be its sole intrinsic goal. However, the concept that the absence of pain and fear constitutes the greatest pleasure, and its advocacy of a simple life, make it very different from hedonism as colloquially understood.