Well, life in 10th century Europe was, indeed, less stressful between plagues and marauders, I guess. I prefer the inquisitive nature of the ancient Greeks and Sumerians. There is some sort of order directing all this apparant chaos, and it is possible to figure it out.

Whether or not the black holes at the center of galaxies eventually consume said galaxy, or why it doesn't fly apart,  is part of the gravity conundrum, and lead to the theories of dark matter and dark energy. Spiral galaxies, anyway.

Black holes cause distortion in space, observable by the light from the stars behind them. Just like the refraction of water tells you it's there. Things you can't see can affect you. Things like gamma rays.

It comes down to "you'll never expand knowlege, if you don't ask questions". People are curious. That's how we got this far. This is an exciting time in physics, and it leaves me scratching my head why Snookie makes headlines, but results from the Large Hadron Colliider don't.