[161] For a good discussion of the growth of population since Spanish conquest down to 1903, see Census of the Philippine Islands, Vol. 1, pp. 442-445. [162] This principle is stated as follows: "The beginnings of social evolution * * * are always to be found in a bountiful environment. Moreover, density of population follows abundance of food, whether the supplies are obtained from the soil directly, or indirectly, in exchange for manufactures; and other things being equal, the activity and the progress of society depend, within limits, on the density of population. A sparse population, scattered over a poor soil, can carry on production only by primitive methods and on a small scale. It can have only the most rudimentary division of labor; it cannot have manufacturing industries, or good roads, or a rapid interchange of intelligence; all of which, together with a highly developed industrial organization and a perfect utilization of capital, are possible to the populations that are relatively dense. A highly developed political life, too, is found only where population is compact. Civil liberty means discussion, and discussion is dependent on the frequent meeting of considerable bodies of men who have varied interests and who look at life from different points of view. Movements for the increase of popular freedom have usually started in towns. Education, religion, art, science, and literature are all dependent on a certain density of population. Schools, universities, churches, the daily newspaper, great publishing houses, libraries, and museums come only when the population per square mile is expressed by more than one unit, and their decay is one of the first symptoms that population is declining. * * *."--Franklin H. Giddings, The Principles of Sociology, (New York, 1911), pp. 366-367. [163] "These changes show how important it was to establish at different points, extending over two hundred miles of the Archipelago, commercial centers, where it was desirable that foreigners should settle. Without these latter, and the facilities afforded to credit which hereby ensued, the sudden rise and prosperity of Iloilo would not have been possible, inasmuch as the mercantile houses in that capital would have been debarred from trading with unknown planters in distant provinces, otherwise than for ready money." Jagor, Travels in the Philippines. (London, 1875), p. 304. Azcarraga, pp. 168-177; 197-198. Le Roy, Bibliographical Notes, 1860-1898.--Bl. and Rb., Vol. 52, pp. 112-114.