A person who thinks all the time
Has nothing to think about except thoughts
So, he loses touch with reality
And lives in a world of illusions
By thoughts, I mean specifically, chatter in the skull
Perpetual and compulsive repetition of words
Of reckoning and calculating
I'm not saying that thinking is bad
Like everything else, It's useful in moderation
A good servant, but a bad master
And all so-called civilized peoples
Have increasingly become crazy and self-destructive
Because, through excessive thinking
They have lost touch with reality
That's to say
We confuse signs
With the real world

Alan Watts