What is the scariest realization you have ever had?
Disclaimer: I'm not an idiot. I promise. Sometimes I just don't think about things, especially when I was younger and still felt immortal.
This was about 7 years ago when I had my eye surgery (similar to Lasik). A few minutes before I went into the room, they handed me a consent form which laid out the possible side effects and complications of my surgery. One of them was that I could possibly go blind as a result. It scared the crap out of me.
Suddenly, I had the realization that anything could go wrong at any point in time (during the surgery, driving a car, walking in the street-anything) and I could get hurt and the doctors may not be able to "put me back together" so to speak. If I was hurt, I might not go back to being 100%. It scared me quite a bit, and caused me to be a much more cautious person in general.
The second most scary thought was in class this last semester. (Quality Improvement in Healthcare.) The topic was consent forms and we were discussing complications and side effects. The teacher asked us if we knew the one complication that EVERY single medical procedure had in common. I was really confused, I mean what possible complication could getying a finger prick for checking your iron, getting a broken bone set amd having heart transplant surgery all have in common?
The answer? Death.
I was floored and suddenly realized, yes, there was always a chance that something could go horribly wrong during any medical procedure and you could die!
TL:DR I realized my own mortality.
Just to clarify, I had never consciously considered myself immortal, but I also never consciously considered myself mortal either.
After years of working with the public every day, I casually said to my boss, "It's weird how two different people can come in with the same question or problem and when I give them both the same answer or assistance, one will leave happy while the other gets frustrated/angry."
Then my boss turned to me and said, "You're just experiencing the epiphany that happens after dealing with the public for too long: Everyone is a little insane in their own way. Different people have different ways of thinking."
When you ponder this idea for awhile, it's pretty terrifying because every day, you have to go out into the world with all these nutcases. There's really nothing stopping anyone from strangling you to death, running you over with their car, picking up a gun and shooting you, etc. They don't even need a reason.
Probably when I'm fighting for my life with an armed intruder, I'm bleeding out quickly due to a severed artery and the realisation after the first punch I gave him that if I didn't give him a second harder punch then I would more than likely die in that room. I mean I'm jetting blood out my left arm, severed tendons in left hand and my attacker still armed with an 8" filleting knife and I've got to knock this prick out. Luckily for me I did. That was a scary realisation, the thought of sudden death, in that moment, a brief millisecond of thought yeah that wasn't good! For full details find my answer to What was the worst crime that victimised you?
That I can be evil sometimes when i'm in a dark mood.
Probably the amount of indifference and contempt most people have for living creatures (all animals including fellow humans).
Also little things like if you think about it pets are really our slaves; though they would often starve/get killed on their own in this day and age, like slaves; they are fed when we decide, we put them in cages and on leashes, and if they want to go somewhere (leave), they are not allowed.
I also think the fact that things like super volcanoes, asteroids, diseases, and problems that we have caused (ozone issues, climate change, etc.) are very real threats to life on earth and very little is being done to prevent and/or reverse them..