Look who was in my greenhouse this morning!
“I am a happy camper so I guess I’m doing something right. Happiness is like a butterfly; the more you chase it, the more it will elude you, but if you turn your attention to other things, it will come and sit softly on your shoulder.”
― Henry David Thoreau
Inspiration in Focus 
So, H.D. Thoreau invented the “I’m a happy camper” phrase. And I would have guessed someone less intellectual–maybe the Kool-ade pitcher guy who went to picnics and pool parties in1960’s television commercials.