 Freedom often means to think and act without restraint. However, living in a society, the freedom of one can affect the freedom of another, and that's a problem. And so we create rules that limit some individual freedoms to make other individual liberties possible. Philosopher Isaiah Berlin hence speaks of two types of liberty, between negative liberty and positive liberty. Negative liberty describes the individual freedom from something, from external constraint and from outside interference. It's the absence of obstacles within a society. Positive liberty means freedom to do something, to act upon one's will, to take control of one's life. It's the possession of the power to proceed regardless of structural limitations in society.