Halliday & Matthiessen (1999: 444):
There are two somewhat distinct versions of this belief. The first is the notion that language distorts reality — or, as a variant of this, that language distorts our thinking (which includes our thinking about reality). This is extra-linguistic deception: language is deceiving us by the way it represents something else. The second is the notion that syntax distorts semantics. This is intra-linguistic deception: language is deceiving us by the way one part of it represents another part.