Under postmodernism many ideas that were seen as objectively true came to be seen as mere constructions of language. Foucault refers to them as ‘discourses’ that construct knowledge. Consequently, since discourses are believed to create and maintain oppression, they have to be carefully monitored and deconstructed. This is not some obscure academic issue, it is the outlook that is behind calls for laws to outlaw speech which may cause offense.