At the beginning of this book I pointed out what I thought was a problem with my use of weed imagery. Clearly there are noxious plants out there in weed flora that inflict (sometimes irreversible) damage on their environment. Linguistic weeds, I suggested, are pesky but never truly pernicious in this way. In fact, linguists would argue they are an essential part of any thriving language. But perhaps not all linguistic weeds are quite so harmless. I'm thinking in this case of aspects of language that have to do with manipulation through advertising and propaganda, of the influence of language on our thinking and behaviour, of linguistic discrimination and, in particular, of official obfuscation and games of status and power. In this next section I want to expose what look to be some really nasty weeds in our language.

The mind and language – mental illness

Dwight Bolinger, in his book Aspects of Language, describes language as being rather like a pair of spectacles through which we view the world. The problem is, of course, that these particular specs aren't made of clear glass.