The whole issue of Justified True Belief and Gettier cases might have something to say about social media such as Facebook and Twitter can deal with the spread of lies and misinformation. Zuckerberg, for instance has tried to make the case that Facebook should not censor content. Yes, one could argue that anyone may say anything they want. But what could be done is if another person challenges that belief, then it is incumbent on the poster of the original content to provide evidence for the claim, otherwise the posting is flagged as challenged and a description of the challenge posted alongside. This is a suggested strategy of how to cope with lies and misinformation without censoring, but it sure is rife with what can be considered Gettier cases. It also poses the two problems: what is a valid challenge? what is a valid justification? How do science and philosophy both deal with those questions?