Thoreau writes in his journal:
It plainly makes men sad to think. Hence pensiveness is akin to sadness. Some dogs, I have noticed, have a propensity to worry cows. They go off by themselves to distant pastures, and ever and anon, like four-legged devils, they worry the cows,—literally full of the devil. They are so full of the devil they know not what to do. I come to interfere between the cows and their tormentors. Ah, I grieve to see the devils escape so easily by their swift limbs, imps of mischief! They are the dog state of those boys who pull down hand-bills in the streets. Their next migration perchance will be into such dogs as these, ignoble fate! The dog, whose office it should be to guard the herd, turned its tormentor. Some courageous cow endeavoring in vain to toss the nimble devil.
