Robert Anton Wilson describes a process of using only the third person in speech and thought for psychological change, and IIRC he got the idea from Alestier Crowley, so the idea could be nearly a century old.
He also extolled the wisdom-widening effect of writing in E-Prime, a subset of the English language that excludes all forms of the verb 'to be': https://en.wikipedia.org/wiki/E-Prime