Group hallucinations

[robvalue]

Also, when the only evidence left is memory, no one can ever be sure whether their memories have been corrupted. Hearing lots of other people speak about what they experienced can retroactively alter people's memories, and so among a large group, they could end up harmonising. The result could end up being nothing like what was actually seen, if anything was there at all.

Of course, people can also lie (to themselves or others) due to peer pressure or not wanting to be left out.

If we’re going by the gospels, no one saw him after his death anyway in the original story. This was added in later.

PS: this doesn’t mean any mass reported unusual viewing is actually wrong, however. It just provides a plausible explanation.