Relativism is the post-modern idea that there can be no absolutes. 20th century philosophers, and especially liberals, expounded on a theory of moral relativism, that there is no absolute right or wrong. Unfortunately, this moral weakening is dangerous, and teaches, in essence, that nothing is wrong, setting mankind ethically adrift.
Liberals sometimes try to give relativism credibility by citing the scientific theory of relativity. For example, Harvard Law School Professor Laurence Tribe argued that the theory of relativity justified finding a right to abortion in the U.S. Constitution.
In a relativistic system, the definitions of words are malleable rather than fixed (see Orwell). Many liberals exploit this malleability to appropriate the means of discourse, causing a word to lose its fixed meaning and instead be arbitrarily assigned a new meaning in keeping with the agenda of the appropriator. For example, the term "racist" once meant someone who discriminated against another based on their race. Due to relativist discourse appropriation, the term has been twisted to mean "one who oppresses other races simply by benefiting in a system that at some point was influenced by racism."
An example of how relativism is deceptive is the manner leftists exploit it to promote the U.S. "Party-switch" myth by claiming that the early Republican Party was "liberal" in the sense that they were supposedly "liberal in the context of their time". In using the term "liberal" in an extremely broad sense while also giving the impression that it refers to the traits of modern-day liberalism, it ignores the fact that the actual policies of the early Republican Party were conservative and parallels the present-day party.
- L. Tribe, "The Curvature of Constitutional Space," Harv. L. Rev. (1989)