Between the philosophy and the science of economics there is neither agreement nor disagreement, but a total heterogeneity, and, therefore, a reciprocal tolerance. It is only when one invades the field, or adopts the methods, of the other, that conflict and error arise. Economics as a science may then deny the legitimacy of the philosophical study of the economic moment; or it may attribute a universal value to its empirical concepts (as it has happened again and again in the disputes between free-traders and protectionists, or as it constantly happens when economic laws are referred to as endowed with a character of absolute necessity); or, finally it may transform its fictions into realities, attributing for instance to the concrete human being, and to the exclusion of any other quality, the qualities it has abstracted for the creation of its homo œconomicus. But, in all such cases, though we may meet these errors among the economists, they are not scientific errors but logical errors; or rather, they are poor science only because they are bad philosophy. The true function of the abstract economic schemes is that of an instrument in the hands of the historical and sociological observer, who needs many other similar instruments, if he wants to gain a concrete and direct knowledge of actual historical and social conditions. It is now time for us to return, from this discussion of the two different elaborations of the economic datum, to a closer consideration of the second form of the practical activity, or of the ethical principle. In the same way as the empirical concepts of economic science are insufficient to exhaust the infinite wealth of the economic principle, no single action or group of single actions can define the ethical principle, which is universal, and therefore merely formal. By identifying the principle with a series, however vast, of particular determinations, that is, by substituting a material ethics for a formal one, we fall back inevitably into utilitarianism, since the volition of a single object or class of objects is not a volition of the universal but of the particular, not an ethical but an economic act. Even the highest forms of moral ideals, such as benevolence, love, altruism, humanitarianism, etc., once they are apprehended materially, and not as mere verbal approximations to the formal ethical principle, acquire a contingent and utilitarian character, and are apt to come in actual conflict with the truly moral will. The same criticism applies, and with greater force, to institutionalized ideals, such as the family, the state, the social organism, the interest of the race, etc.; none of them can be the object of the moral will without exceptions and restrictions, that is, without losing in the act of the will its institutional character, and appearing as one of the particular conditions under which the particular moral volition takes place. The religious principles themselves are subject to this reduction