The determination of fact is not a decision. We don’t get to decide facts. We recognize them. Sometimes, data is needed to illustrate a fact. And we humans have to be logical enough to see when sufficient data is present for the establishment of a factual conclusion. If you don’t have data to prove the fact, then you’re dealing with conjecture, supposition, prejudice, simple opinion, or something else. But if the data illustrates the fact, then Facebook, politicians, you, me or anyone is obligated to respect it.
The earth is round and not flat. The data is the experience of countless people who have travelled around it to arrive where they started, as well as pictures from space and other scientific measurements. That is a fact. It’s not up to people to decide if they believe. Reporting the earth is flat, or blatantly disregarding other well known facts in order to make a subsequent argument or support a political view is wrong. Facebook is obligated to prevent the spread of such lies wherever it can. This is in the interest of truth, professional journalism and the fundamental health of societal discourse.