Re: Just ask it
[I]f the answer is yes and, indeed, if the answer is no it is most likely not ChatGPT.
I played with it a little bit, and one thing I could never manage was to make it give a simple, straightforward answer. Certainly it never gave me a yes/no answer to a yes/no question. Of course, this is a direct consequence of how it works: the basic algorithm is something like "what is the most probable next token (where token = a word, a phrase, or punctuation) that would follow this text fragment (prompt) based on the statistics of the corpus of text that is your training set?" I find it rather amazing that the algorithm that can be stated in a single simple sentence would give such good results just because you get good statistics from a large enough sample. But once it comes up with a few sentences it never reduces the answer to something simple like yes or no or maybe.
Rather, ChatGPT sounds to me like a rather bad grammar school teacher who repeats memorized texts no matter what the question is. If you pardon what sounds like a pun but is actually quite serious, it sounds robotic.
So you can ask it if it wrote something, but then it will be up to you to decipher the answer that is likely to cover every possibility.