To explain:—The Newtonian Gravity—a law of Nature—a law whose existence as such no one out of Bedlam questions—a law whose admission as such enables us to account for nine-tenths of the Universal phænomena—a law which, merely because it does so enable us to account for these phænomena, we are perfectly willing, without reference to any other considerations, to admit, and cannot help admitting, as a law—a law, nevertheless, of which neither the principle nor the _modus operandi_ of the principle, has ever yet been traced by the human analysis—a law, in short, which, neither in its detail nor in its generality, has been found susceptible of explanation _at all_—is at length seen to be at every point thoroughly explicable, provided only we yield our assent to——what? To an hypothesis? Why _if_ an hypothesis—if the merest hypothesis—if an hypothesis for whose assumption—as in the case of that _pure_ hypothesis the Newtonian law itself—no shadow of _à priori_ reason could be assigned—if an hypothesis, even so absolute as all this implies, would enable us to perceive a principle for the Newtonian law—would enable us to understand as satisfied, conditions so miraculously—so ineffably complex and seemingly irreconcileable as those involved in the relations of which Gravity tells us,—what rational being _could_ so expose his fatuity as to call even this absolute hypothesis an hypothesis any longer—unless, indeed, he were to persist in so calling it, with the understanding that he did so, simply for the sake of consistency _in words_? But what is the true state of our present case? What is _the fact_? Not only that it is _not_ an hypothesis which we are required _to adopt_, in order to admit the principle at issue explained, but that it _is_ a logical conclusion which we are requested _not_ to adopt if we can avoid it—which we are simply invited to _deny if we can_:—a conclusion of so accurate a logicality that to dispute it would be the effort—to doubt its validity beyond our power:—a conclusion from which we see no mode of escape, turn as we will; a result which confronts us either at the end of an _in_ductive journey from the phænomena of the very Law discussed, or at the close of a _de_ductive career from the most rigorously simple of all conceivable assumptions—_the assumption, in a word, of Simplicity itself_. And if here, for the mere sake of cavilling, it be urged, that although my starting-point is, as I assert, the assumption of absolute Simplicity, yet Simplicity, considered merely in itself, is no axiom; and that only deductions from axioms are indisputable—it is thus that I reply:—