This animistic prepossession seems to pervade the earlier of his two monumental works in a greater degree than the later. In the _Moral Sentiments_ recourse is had to the teleological ground of the natural order more freely and with perceptibly greater insistence. There seems to be reason for holding that the animistic preconception weakened or, at any rate, fell more into the background as his later work of speculation and investigation proceeded. The change shows itself also in some details of his economic theory, as first set forth in the _Lectures_, and afterwards more fully developed in the _Wealth of Nations_. So, for instance, in the earlier presentation of the matter, "the division of labor is the immediate cause of opulence"; and this division of labor, which is the chief condition of economic well-being, "flows from a direct propensity in human nature for one man to barter with another."[8] The "propensity" in question is here appealed to as a natural endowment immediately given to man with a view to the welfare of human society, and without any attempt at further explanation of how man has come by it. No causal explanation of its presence or character is offered. But the corresponding passage of the _Wealth of Nations_ handles the question more cautiously.[9] Other parallel passages might be compared, with much the same effect. The guiding hand has withdrawn farther from the range of human vision. However, these and other like filial expressions of a devout optimism need, perhaps, not be taken as integral features of Adam Smith's economic theory, or as seriously affecting the character of his work as an economist. They are the expression of his general philosophical and theological views, and are significant for the present purpose chiefly as evidences of an animistic and optimistic bent. They go to show what is Adam Smith's accepted ground of finality,--the ground to which all his speculations on human affairs converge; but they do not in any great degree show the teleological bias guiding his formulation of economic theory in detail.