Linus Torvalds, the Linux kernel creator, in responding to a complaint why the kernel has evolved via "sheer luck", has this interesting view about engineering complex things. An Excerpt in italic:
"...You know what the most complex piece of engineering known to man in the whole solar system is?
Guess what - it's not Linux, it's not Solaris, and it's not your car.
It's you. And me.
And think about how you and me actually came about - not through any complex design.
Right. "sheer luck".
Well, sheer luck, AND:
- free availability and _crosspollination_ through sharing of "source code", although biologists call it DNA.
- a rather unforgiving user environment, that happily replaces bad versions of us with better working versions and thus culls the herd (biologists often call this "survival of the fittest")
- massive undirected parallel development ("trial and error")..."
The same process probably underlies the relative success of capitalism. Of course, capitalism might be too successful and hastens our species' extinction.