 Lewis and Langford (1932) are led to conclusions which are not dissimilar to those of Behmann. According to them, the paradoxes show that certain expressions do not express propositions. They adopt the notation \(p : \alpha\) to mean that \(p\) is a name whose meaning is the proposition \(\alpha\) (so \(p\) and “\(\alpha\)” denote the same entity and can replace each other); typically the Liar amounts to “\(p: p\) is false”, but we can also imagine more complex self-referential situations, for instance: