The sentence "anything is anything" is not a stable tautology, but a multileveled contraction. As a banner, it is self-vitiating, but it exploits the "weakness" of language to provide a meta paradox.

It can be read as

[a] generically, any "thing" is itself [-true by "definition"]

[b] anything explicitly is any other thing. the entire continuum may be mapped onto itself in any way. traditionally, this is only true if the continuum is empty. if the continuum was empty, then where would the meaning of assertion come from? [-false by "definition"]

[c] "anything can be converted into or seen functionally as anything else". This is the position of both transcendental religion and of rationalism. rationalism factors out opaque areas, so that, with correct transformation rules, it can convert any meaning or thing into any other thing. even if the effort to do so is incalculable. [-Undecidable]

"Anything is anything" is an assertion which can't be checked, since the three interpretations are in contradiction; yet there is no dissasociation between language and reality. You can't find an instance of "zero" in the world, but you can easily find an "anything" - an underspecified signifier.