possible in those early stages when all the energies of men are taken up in the primary business of preserving and maintaining life. So it was that war had a beginning in human history. Is it unreasonable to suppose that it will also have an end? There is another way, besides that of counting the world's war-years, to determine the probability of the diminution and eventual disappearance of war. We may consider the causes of war, and the extent to which these causes are, or are not, ceasing to operate. Dr. Woods passingly realises the importance of this test and even enumerates what he considers to be the causes of war, without, however, following up his clue. As he reckons them, they are four in number: racial, economic, religious, and personal. There is frequently a considerable amount of doubt concerning the cause of a particular war, and no doubt the causes are usually mixed and slowly accumulative, just as in disease a number of factors may have gradually combined to bring on the sudden overthrow of health. There can be no doubt that the four causes enumerated have been very influential in producing war. There can, however, be equally little doubt that nearly all of them are diminishing in their war-producing power. Religion, which after the Reformation seemed to foment so many wars, is now practically almost extinct as a cause of war in Europe. Economic causes which were once regarded as good and sound motives for war have been discredited, though they cannot be said to be abolished; in the Middle Ages fighting was undoubtedly a most profitable business, not only by the booty which might thus be obtained, but by the high ransoms which even down to the seventeenth century might be legitimately demanded for prisoners. So that war with France was regarded as an English gentleman's best method of growing rich. Later it was believed that a country could capture the "wealth" of another country by destroying that country's commerce, and in the eighteenth century that doctrine was openly asserted even by responsible statesmen; later, the growth of political economy made clear that every nation flourishes by the prosperity of other nations, and that by impoverishing the nation with which it traded a nation impoverishes itself, for a tradesman cannot grow rich by killing his customers. So it came about that, as Mill put it, the commercial spirit, which during one period of European history was the principal cause of war, became one of its strongest obstacles, though, since Mill wrote, the old fallacy that it is a legitimate and advantageous method to fight for markets, has frequently reappeared.[1] Again, the personal causes of war, although in a large measure incalculable, have much smaller scope under modern conditions than formerly. Under ancient conditions, with power centred in despotic monarchs or autocratic ministers, the personal causes of war counted for much. In more recent