On the Wikipedia entry on Vesna Voluvic, who holds the Guiness book work record on surviving the highest fall without a parachute, a conspiracy theory claiming the plane got shot by the army got debunked as follows:

One source does not support such conspiracy theories and quotes Czech army expert: In case of violation of the air space, the incident would not be solved by anti-air missiles, but by fighter planes. Also it would not be possible to conceal such incident, as there would approximately 150–200 people knowing about the incident. They would not have any reason to not tell about incident today.

It is not the only claim that debunked the conspiracy theory, so I am not reinstating this conspiracy theory. However, the claim that 150-200 would not be able to keep a secret after such a long time, doesn't look strong to me. I can imagine various intelligence organisation having much more staff at hand. Is there any evidence or theory that give a general estimate on how many people it takes to keep a secret? I would suspect that number to be quite high, since only Snowden and Assenge comes to mind in modern history, contradicting the Czech source that with 150-200 people it wouldn't be possible to keep a secret.

  • 1
    How exactly do you expect this to be objectively answered? Sometimes one person can't even keep their own secret.
    – meagar
    May 26 '14 at 16:15
  • 1
    @meager sure, but there must be risk-assessment models for governments to assess their risk, and it could perfectly be that the number is indeed below 150.
    – Andra
    May 26 '14 at 16:18
  • 3
    "Three may keep a secret, if two of them are dead." Benjamin Franklin, Poor Richard's Almanac (1700s, reprinted 1914 USC Pub. Co.), Item #559
    – Paul
    May 27 '14 at 2:12
  • 5
    Related question: How many people have to know before it's not considered a secret any more?
    – Bobson
    May 27 '14 at 4:28
  • @Bobson, Now that is a more interesting question, I think. More suited to philosophy.SE than here, but still an interesting question.
    – Brian S
    May 27 '14 at 15:00

Browse other questions tagged .