2. Consumption is either _voluntary_ or _involuntary_. Of the latter kind we have instances in the _natural decay_ of objects, as in wood and vegetables; the rusting of iron, the mildew and the moth-eating of cotton and woolen fabrics, and the wearing away by attrition of gold, silver, and other metals; also the destruction caused by vermin. Much of this may be prevented by the prudent foresight which sound economy enjoins; yet much loss will inevitably take place. A great deal of consumption is _accidental_. Great destruction is caused by fires, steam-boiler explosions, floods and tornadoes, earthquakes and volcanic eruptions. 3. Voluntary consumption is either _productive_ or _unproductive_. The former is when the material appears in new form and with a higher value, as cloth made into garments and iron into hardware and cutlery. Unproductive consumption occurs, both in the cases before mentioned of natural and accidental consumption, and in cases where gratification of desire is the sole object sought and achieved, as when one eats and drinks simply for the enjoyment, and without reference to the waste of nature or the nourishment of the system. It is not altogether easy to discriminate between these two kinds of consumption. We readily see the difference between a man’s drinking a quantity of whiskey, not because it will help him in the performance of any duty, but because he likes it, and the scattering of a quantity of seed over the ground in spring. There is no doubt that one act is productive and the other unproductive. But there are cases where the distinction is less clear. It is not necessarily a case of unproductive consumption when one destroys value for the sake of gratifying some desire. Probably a majority of men eat and drink simply because they desire food and drink, having no thought of any ulterior object. Yet this eating and drinking is absolutely essential to productive labor. The wealth consumed in this way reappears, to a large extent, in the products of human industry. Still there is much really unproductive consumption; a destruction of value, in the place of which no other value ever appears. There are, for instance, men and women— * * * “who creep Into this world to eat and sleep, And know no reason why they’re born, But simply to consume the corn.” Vast quantities of wealth are consumed in riotous living, in greedy and vulgar extravagance, and unmeaning magnificence. There is also much consumption designed to be productive, but failing of its end through misdirection. Large amounts of property are sometimes invested in enterprises which prove failures. This occurs partly from miscalculation or negligence, and partly from a disposition to trust to chances—the gambler’s calculation. In these ways much wealth is consumed with no consequent product.