As Joonas said, ipse is an intensifier, not a pronoun in and of itself.
Caesar ipse hoc dixit.
Caesar himself said this!
The trick is, Latin leaves out pronouns all the time. So you'll sometimes see ipse standing on its own.
Ipse hoc aedificavi.
I built this myself!
Here, the ending of the verb is what supplies the "I" and "my-" parts.
Finally, a word of caution: ipse does not mean "-self" in the sense of "he's talking to himself". In English, the "intensive" pronoun and the "reflexive" pronoun look the same, but in Latin this isn't the case! So only use ipse when you're emphasizing something, not when you're saying that the subject and the object are the same.