Or, where do all the twigs go?
'It's to do with human nature and has nothing whatever to do with science,' says Peter, my logical friend. 'There is a certain density of twigs on the ground that promotes their being picked up. When the density is great enough someone in authority says "The twigs must go." Before the order from above, you never notice them.'
So, really, we are talking about dependence on power and a need to be controlled. 'It's purely psychological,' says Peter, as if closing the book. But what I'd like to say is, psychology is a science. And it has everything to do with gardening.