And yet, who knows the heart of a bird? A child, possibly, or a poet; certainly not a philosopher. And happiness, too,--is that something of which the scientific mind can render us a quite adequate description? Or is it, rather, a wayward, mysterious thing, coming often when least expected, and going away again when, by all tokens, it ought to remain? How is it with ourselves? Do we wait to weigh all the good and evil of our state, to take an accurate account of it _pro_ and _con_, before we allow ourselves to be glad or sorry? Not many of us, I think. Mortuary tables may demonstrate that half the children born in this country fail to reach the age of twenty years. But what then? Our "expectation of life" is not based upon statistics. The tables may be correct, for aught we know; but they deal with men in general and on the average; they have no message for you and me individually. And it seems not unlikely that birds may be equally illogical; always expecting to live, and not die, and often giving themselves up to impulses of gladness without stopping to inquire whether, on grounds of absolute reason, these impulses are to be justified. Let us hope so, at all events, till somebody proves the contrary.
But even looking at the subject a little more philosophically, we may say--and be thankful to say it--that the joy of life is not dependent upon comfort, nor yet upon safety. The essential matter is that the heart be engaged. Then, though we be toiling up the Matterhorn, or swept along in the rush of a bayonet charge, we may still find existence not only endurable, but in the highest degree exhilarating. On the other hand, if there is no longer anything we care for; if enthusiasm is dead, and hope also, then, though we have all that money can buy, suicide is perhaps the only fitting action that is left for us,--unless, perchance, we are still able to pass the time in writing treatises to prove that everybody else ought to be as unhappy as ourselves.
Birds have many enemies and their full share of privation, but I do not believe that they often suffer from _ennui_. Having "neither storehouse nor barn,"[15] they are never in want of something to do. From sunrise till noon there is the getting of breakfast, then from noon till sunset the getting of dinner,--both out-of-doors, and without any trouble of cookery or dishes,--a kind of perpetual picnic. What could be simpler or more delightful? Carried on in this way, eating is no longer the coarse and sensual thing we make it, with our set meal-times and elaborate preparations.