Aliens

The reason, We don't hear from Aliens is, that one of two things can happen to a society; 

Either it,

A. Organises in favor of gratitude(veto in favor of gratitude), and becomes so healthy, that it, by default never organises enough to build a radio.

or. 

B. It starts organising in favor of law, and that it; " Can’t be a pity", like our democracy, to which a civilisation,  simply, dies out, due to degeneration.

Simply because, Nature is; Flora, fauna and hunters, and that, in an unhealthy society, the hunter is isolated,  let alone killed.

By personal estimates, our species has far less than 30.000 years left, before we're degenerated so far, that we simply just snuff it.

"I know he's not much to look at, friend, but he's only got 7 diagnoses, and I wanna be a mum, so.."

- Between friends, 4-5000 A.D.

Sims

DAD