You can divide reasoning into three levels:
1) Can't reason - just regurgitates from memory
2) Can reason, but makes mistakes
3) Always reasons perfectly, never makes mistakes
If an LLM makes mistakes, you've proven that it doesn't reason perfectly.
You haven't proven that it can't reason.
But: Plenty of people struggle with playing along with Socrates' method. Can they not reason at all?
I hope you can translate the conversation of philosophist vs chatgpt from Russian [1]. The conversation from the philosopher is built due to Socrates' method but chatgpt can not even react consistently.
> Plenty of people struggle with playing along with Socrates' method. Can they not reason at all?
I do not hold the opinion that chatgpt "struggles" with Socrates' method, I am clearly seing it can not use it at all even from answering side of Socrates' dualogue which is not that hard. Chatgpt can not use Socrates' method from questioning side of dialogue by design because it never asks questions.
[1] https://hvylya.net/analytics/268340-dialogi-sergeya-dacyuka-...