What is the act of self-referencing?

Question

Ok, so something can be self-referencing.

"This sentence contains thirty-eight letters."

or

"This is not a pipe."

But what is "doing that" called?

Along the lines of how self-deprecating is self-deprecation.

Thought maybe… self-referenciation, but that doesn't seem to exist. How ironic.

Answer 1

The OED's definition of self-reference includes a mention of propositions and paradoxes, making it especially apt for your two examples:

Reference to oneself or itself; the direction of one's attention at oneself, esp. in forming a comparative assessment of one's characteristics or experience; spec. in Philos., the characteristic or quality of referring to itself contained in certain paradoxes, propositions, or statements.

To answer your question, then, I guess the act of self-reference is called a self-reference.

My favorite self-referencing paradox goes something like this:

Answer 2

The term you're looking for is self-reference.

"This is a sentence."
Ah, I like it when an example makes a self-reference.