There's kind of a difference here between witnessed and took part in.
It's we're talking took part in, then there's not even a question for me. I would have wanted to walk on the moon. For my money it's still the single greatest accomplishment that mankind has ever managed. We sent our exemplars to another celestial body where they had to bring every single thing they would ever need (food, water, wait, shelter, all of it), let them wander around (for as much as three full days - check it), and brought them all back safely.
It's an achievement that will be phenomenal to see if we ever manage to top it, and it's still an event that leaves me speechless. I currently have a book of moon landing photos checked out. I've checked it out a half dozen times. There is nowhere or nowhen that I would rather be...or to have been.
Now, in terms of events that I would have wished to witness happening...
Two answers...the first one is to say any of hundreds of hypothetical/mythical/miraculous events from religions. If I could include the qualifier of 'whichever religion is right', then I would want to see some undeniable, absolute proof that religion is correct. I'd be fine seeing God (or whichever god) create the universe or Earth or life or whatever. I'd be fine seeing Jesus's loaves and fishes or to watch his tomb for three days. I'd be fine to see - and be able to comprehend - anything proving beyond any doubts that some religion (and I don't care which one - I don't have a dog in this fight). I have absolutely no faith in religion, believe that science and random chance over a long time span, and I would be fascinated to hear that I have been wrong low these many years.
On the third hand, if I had to go with picking a real, historical, definitive date, that's tougher.
It's tough to pick any science experiments because so many of the that we speak of as being singular events aren't really singular events. They're experiments that come out oddly, are repeated, and are are eventually explained over the next few weeks or months. There is rarely a singular event to see with those.
Some of the historical dates that I would want to see, that are among the most important, were also probably rather nondescript. I'm thinking here of the first books being printed by Gutenberg. The actual event itself probably wasn't the fantastic spectator event that a wish like this one should be preserved for.
Maybe I'd go for seeing the Kennedy assassination. It would be nice to once and for all know who shot Kennedy and from where. I could take back recording equipment (if it's within the rules of the wish) and solve the mystery once and for all.
I'm thinking going back to Roanoke to see what happened to the settlers could perhaps be a bit unsafe for me, assuming that I would be physically present at the event I am witnessing. Since we don't know what happened, I'll assume that I would be vulnerable to it happening to me, as well.
Seeing Columbus come ashore on the new world would be pretty impressive.
Witnessing a great sporting event - Babe Ruth's called shot, Bill Mazeroski's home run, the Milan championship basketball game, the Mexico City Olympics with Bob Beamon's long jump for the ages, seeing Larry Bird's duel against Dominique Wilkins in the playoffs, any of Pete Maravich's games, Jordan's 63 in the Garden, Wilt's100, Reggie Jackson's 3 HR World Series game, Pudge's HR in the '75 World Series - would be neat to see, but this one calls, I think, for something grander.
When it's all said and done, I think I would have to pick something that was a singular event, one that we know to be stirring, emotionally rousing, and historically important. That leads me to think about being in the audience for a great speech. As to which one, I'll pick one that's admittedly fairly recent in terms of the scope of human history, but it's the one that exemplifies great speeches to me: MLK's "I Have a Dream" speech on the steps of the Lincoln Memorial.
The combination of setting (flanked by Lincoln, the Washington monument, the reflecting pool, the capitol), the speaker (MLK's cadence throughout this one is note perfect), the gravitas of the moment (the pinnacle of nonviolent protest against racial injustice in America) makes this my choice.
I would wish to have been a member of the audience for MLK's "I Have a Dream" speech.
In case you're late to the party, here's the deal...
Here's what I've answered so far...
- #25 - "I Know What Love Is" by Don White (way more detail here)
- #35 - no business (more details here)
- #36 - MLK, Jr's "I Have a Dream" speech on the National Mall