[[wikipedia:Newspeak|Newspeak]] is a language primarily designed to support [[doublethink]]. In general it is very hard to think about things that you cannot speak about, express in a language. If you control the language you can basically control what people can (easily) think about. The concept has been taken to its extereme in [[1984]] novell by George Orwell, however every society is in some way relying on this and uses language to supress unwanted thoughts.