In philosophy, determinism is the thesis that there are conditions that make future events happen the way they happen. Today, the term is mostly used in natural philosophy: there are natural laws and causality that govern certain aspects of nature. Some of those laws are not probabilistic, they apply all the time. The opposite position to this idea is called indeterminism. If there are really conditions that cause future events to be uniquely determined in advance, this will cause problems supporting the idea that there is free will. Other ideas that need the thesis of determinism are called fatalism and predestination.