1. Yeah, this will probably be an accepted fallacy for day to day usage. You could quote leading geologists/physicists and the implication is that they have a v

1. Yeah, this will probably be an accepted fallacy for day to day usage. You could quote leading geologists/physicists and the implication is that they have a vested interest in being correct. But the reasoning there isn't just "Because they're experts, so trust them!", it's "They purport to have measured it and I trust that they did so accurately because of their position as leaders of their field and their desire to remain as such.". Still technically might be a fallacy, but I would accept it in the case of a casual conversation about the Earth's circumference. 2. Agreed that it's contextual. I merely wanted to point out that not all discrediting is ad hominem as you seemed to imply. 3. Also agreed that it's highly dependent on context. Again, just pointing out that one can speak out about policy direction without committing a fallacy. And yes, I dislike that as well! The fallacy fallacy: https://yourlogicalfallacyis.com/the-fallacy-fallacy https://yourlogicalfallacyis.com/the-fallacy-fallacy