What are plants doing? What are plants all about? They serve human beings by being decorative, but what is it from its own point of view? It's using up air; it's using up energy. It's really not doing anything except being ornamental. And yet here's this whole vegetable world, cactus plants, trees, roses, tulips, and edible vegetables, like cabbages, celery, lettuce - they're all doing this dance.
The nature of man (ed. 1975)