If you wanna go around arguing the Earth is flat, you need to have something more persuasive than 'do the research.' Not that you personally believe in a flat earth, but it's a good example of why we shouldn't treat epistemological uncertainty as the starting point; there is so much evidence for Earth being round and so little offered in favor of it being flat that its roundness should be treated as a fact unless extraordinary new evidence to the contrary is produced. If someone comes along insisting on its flatness without overcoming that bar, then it's OK to treat them as either a fool or a troll and reject their opinions.