This and that
This sentence does in fact not have the property it claims not to have.
— Robert Boeninger
A wonderful example of a not so obvious self-contradictory sentence. It is discussed in Metamagical Themas: Questing for the Essence of Mind and Pattern by Douglas R. Hofstadter. Some more examples of paradoxical statements, a great illustration of troublesome self-reference, and why it simply is all about this and that may be found in the h2g2‘s entry on “self-reference“.