This is a fascinating and funny article explaining the Dunbar number – the maximum practical number of real ‘friend’ relationships you can sustain at any given moment in time.
Think about this the next time you get really pissed off in traffic, when you start throwing finger gestures and wedging your head out of the window to scream, “LEARN TO FUCKING DRIVE, FUCKER!!” Try to imagine acting like that in a smaller group. Like if you’re standing in an elevator with two friends and a coworker, and the friend goes to hit a button and accidentally punches the wrong one. Would you lean over, your mouth two inches from her ear, and scream “LEARN TO OPERATE THE FUCKING ELEVATOR BUTTONS, SHITCAMEL!!”
They’d think you’d gone insane. We all go a little insane, though, when we get in a group larger than the Monkeysphere. That’s why you get that weird feeling of anonymous invincibility when you’re sitting in a large crowd, screaming curses at a football player you’d never dare say to his face.