1. Odds are with the house in a purely numbers game. Would you play craps with the odds against you being billions to 1? May as well spend your money on strippers if you’re in Vegas.
2. Sightings of unexplained objects seen in the sky. Any time aliens or UFOs are mentioned in any given group of people there is always that one guy who saw something one night in college. Always. So many individuals in the population have seen something their personal knowledge and logic can’t explain that the only explanation is the unknown.
3. US cover ups of downed “weather balloons” and “experimental military aircraft.” On principle alone, when information is covered up or hidden, there’s something more at work there. Big brother has made so many attempts to hide what is happening. Knowledge about downed weather balloons isn’t so shocking or detrimental to the people that it warrants such secrecy.
4. Influences on world culture in ancient times. An outside entity that was able to influence cultures across the world in similar fashions cannot be reasonably explained. Such similar folklore and beliefs, although called by different names, has such similarity that the only explanation is the same influence. The only influence with the technology to travel the world to visit these societies is aliens.
5. Meet my grandmother.
6. Testimonials from people all over of their experiences with the grays. Their stories of what happened during their contact are so similar, even if people are afraid or embarrassed to share their entire story until someone else shares their personal experiences. The same things happened to so many people that it must have been the same contact.