Is "thinking things through" a lost art?

are strong and wrong over those who are weak and right. "

I think Twitter contributed to the trend in a large way. People became conditioned to say something memorable in 144 characters rather than have substantive conversations.

And there used to be a lot of discussion boards on the internet where you could have extended conversations on any topic you chose to start. But for the most part, the role of those have been taken over by mindless Disqus flame wars over particular articles.

It takes bandwidth and memory to run a discussion board and they don't turn a profit like an article site with Disqus arguments to draw people in.

The problem of short sighted (and short-sited)* thinking is not new.
People act in desire of some results.

These results may be just what we expected (wanted, hoped); cross the road, catch the bus to work.
They may be even better; cross the road and a passing friend gives you a ride.
They certainly can be worse and unwanted; cross road, bus never comes, you get fired for lateness.
Or, they may be totally disconnected, unexpected and un-thought; you fall into a sinkhole and never get across the road.

The results of actions can be seen; they may also be unseen. Wants motivate our acts. Results are of two kinds; desired and undesired.
Thus we bounce and ricochet off the rails of "oops!" and "Did I do that?
Perhaps if humans successfully saw through all thoughts, we would all stop stupid** activities.

*Think selfishness, situated in personal desires
** Think useless