@Gustavo, Co-Moderator posted:
The sentence you quoted lacks the main verb, which I added above.
"Ones" is correct there because it substitutes for "thoughts," with the zero article. You would need "the ones" if "the thoughts" were required:
The difference between ones that I endorse and others I don't and the ones I endorse and the ones I don't is that the first classification is open (there may be a third group of ideas the person only endorses (or doesn't endorse) partially, while the second one is a closed classification.
I really appreciate your help. Now I can feel the difference.
I have another thing I still don't understand. Could you explain it for me?
Unlike your saying <"thoughts," with the zero article> , the reason I thought <ones> could be replaced by < those> or <the ones> is because of the article , which is <On the contrary, many of the thoughts>. Then doesn't it matter whether <the> before a noun mentioned before is or not?