Postmodernism is a philosophical position that questions the certainty and immutability of human knowledge. It emerges in opposition to the main tenets of modernism and rejects claims of objective universal truths that are not bound and shaped by the social, historical, political and cultural context in which they arise. Postmodernist attitudes are characterized by moral relativism, a view where opposite moral precepts and world views are equally valid regardless of their consequences or scientific underpinning. This has led to criticism from thinkers that subscribe to rationalism and the notion that objective truths can be derived from scientific rigor.