My time is unfortunately too short to stay and give to this truth the development it deserves; but I will assume that you grant it without further parley, and pass to the next step in my argument. And here, too, I shall have to bespeak your close attention for a moment, while I pass over the subject far more {125} rapidly than it deserves. Whether true or false, any view of the universe which shall completely satisfy the mind must obey conditions of the mind's own imposing, must at least let the mind be the umpire to decide whether it be fit to be called a rational universe or not. Not any nature of things which may seem to be will also seem to be _ipso facto_ rational; and if it do not seem rational, it will afflict the mind with a ceaseless uneasiness, till it be formulated or interpreted in some other and more congenial way. The study of what the mind's criteria of rationality are, the definition of its exactions in this respect, form an intensely interesting subject into which I cannot enter now with any detail.[7] But so much I think you will grant me without argument,--that all three departments of the mind alike have a vote in the matter, and that no conception will pass muster which violates any of their essential modes of activity, or which leaves them without a chance to work. By what title is it that every would-be universal formula, every system of philosophy which rears its head, receives the inevitable critical volley from one half of mankind, and falls to the rear, to become at the very best the creed of some partial sect? Either it has dropped out of its net some of our impressions of sense,--what we call the facts of nature,--or it has left the theoretic and defining department with a lot of inconsistencies and unmediated transitions on its hands; or else, finally, it has left some one or more of our fundamental active and emotional powers with no object outside of themselves to react-on or to live for. Any one of these defects is fatal to its complete success. Some one {126} will be sure to discover the flaw, to scout the system, and to seek another in its stead. I need not go far to collect examples to illustrate to an audience of theologians what I mean. Nor will you in particular, as champions of the Unitarianism of New England, be slow to furnish, from the motives which led to your departure from our orthodox ancestral Calvinism, instances enough under the third or practical head. A God who gives so little scope to love, a predestination which takes from endeavor all its zest with all its fruit, are irrational conceptions, because they say to our most cherished powers, There is no object for you.