Two travellers, walking in the noonday sun, sought the shade of a widespreading tree to rest. As they lay looking up among the pleasant leaves, they saw that it was a plane tree. "How useless is the plane!" Said one of them. "It bears no fruit whatever, and only serves to litter the ground with leaves.""Ungrateful creatures!" Said a voice from the plane tree. "You lie here in my cooling shade, and yet you say I am useless! thus ungratefully, o jupiter, do men receive their blessings!" 
Our best blessings are often the least appreciated. 