The origin of the phrase "I have a body"

[Speakpigeon]

Read Descartes again. He took the pain to explain at length that by "I" he just meant the "thinking thing".
EB

"Thing", eh? So, what he demonstrated with thinking is a thing exists?

Sorry, I'm French, I can't answer questions in drunken English.

Is the "I" something "that which I can perceive"? Or is it not? I'm betting not!

I take it you are aware of your thoughts, and this is as good as any perception could possibly be. Now, just call your thoughts, "I". And that's it. Me, I don't see what's wrong with that, irrespective of whether or not the mind is something else than brain processes.
EB

Who’s the thinker of the thoughts if the thinking thing is my thoughts?

I don't know what you mean by "thinker" but I'm not going there. I was interested in correcting you concerning your pronouncements about what Descartes said. If the restaurant doesn't propose chicken it's not use ordering chicken with ketchup.
EB