But mark, it is still "_an assumption_,"[437] and the central question around which the battle must be fought is, _What ground have we for the assumption that the order of nature is so absolutely persistent and changeless that it never has been and never can be interfered with by an act of intelligent volition?_ Dr. Tyndall has attempted an answer to this question. We shall endeavor, first, clearly to comprehend his answer, and, secondly, to estimate its logical validity. 1. He tells us that the belief in a changeless order of nature "is a kind of inspiration." "The passage from facts to principles (that is, the passage from our limited experience of uniformity to the affirmation of universal and permanent order) is called induction, which in its highest form is inspiration."[438] This, however, is poetry, and not science. This inductive inference embraces vastly more in the conclusion than is contained in the premises; the antecedent is limited, the consequent is unlimited; and the only warrant that Dr. Tyndall has for the violation of the most fundamental logical canon is "inspiration." But, whatever Dr. Tyndall may understand by this ambiguous phrase, it is certain that his own mind is not satisfied, and so he tries again. 2. He tells us that this belief rests upon the long-continued observations, registered experiences, and experimental verifications of a succession of scientific men, as Galileo, Torricelli, Pascal, Kepler, and Newton. But here again the experiences are limited, and do not justify a universal conclusion; and Dr. Tyndall himself is not satisfied. He says, "The scientific mind can find no repose in the mere registration of sequences in nature. The further question obtrudes itself with resistless might, _Whence come the sequences?_ What is it that binds the consequent with the antecedent in nature?" What is it, we ask with redoubled earnestness and emphasis, which authorizes our drawing a universal conclusion from particular premises? "The truly scientific intellect never can attain rest until it reaches the FORCES by which the observed succession is produced.... Not until the relation between the forces and the phenomena has been established is the _law of the reason_ rendered concentric with the _law of nature_, and not until this is effected does the mind of the scientific philosopher rest in peace."[439] Here we have "the law of the reason" substituted for "the highest form of inspiration," and we are curious to learn what this "law of the reason" is. Is it the principle, or law of causality--namely, that "all phenomena present themselves to us as the expression of _power_, and refer us to a causal ground?" But this law of the reason says nothing about uniformity. The same power may produce a diversity of effects. "Infinitely numerous and various universes might have been fashioned by the various distribution of the original nebulous matter, although the particles of matter should obey the one law of gravity."[440]