ical to extend a merely empirical law beyond the limits in which it has been found true by observation. It was once believed, for instance, that all swans are white, and, what is more, the belief was sustained by the uniform experience of mankind for thirty centuries; but it turned out to be erroneous, all the same. That the black swan of archebiosis has not been seen is no proof that it may not-be seen, if we push on to its presumptive haunt by the shaded springs of life; and, in the interval, we can be sure only of what we have positively seen. But of this there of course can be no doubt. The famous maxim, All life proceeds from life, is indeed necessarily true of all the more specialized forms of life, because the proceeding of any one of these directly from inorganic matter would necessitate a leap over the intermediate forms; and Nature, as in our day is realized more vividly than before, does nothing by leaps. The maxim, though reached inductively, may be explained deductively; it is itself, thus limited, a corollary from the general law of evolution. But, with forms of life having little or no specialization, and only a few removes or one remove from inorganic matter, the case is plainly different. Respecting these, induction, so far as it has yet gone, and deduction, so far as it can now be applied, agree in pointing unmistakably to their origin in the unorganized matter from which they are scarcely distinguishable, and from which they differ in every respect vastly less than from the more specialized forms arising out of them, and immeasurably less than the human adult differs from the human embryo. Of these lowest forms, exhibiting life almost or quite without organization, the maxim not only is not necessarily true, but is necessarily untrue. It applies, as it must ever apply, to living things in general, but not to those living things which exemplify the bottom characteristics of the group. Omne vivum ex vivo was not written of the type. If it were, ex nihilo nihil fit could not be written too.
"According to the material contention," avers Dr. Beale, "everything owes its existence to the properties of the material particles out of which it is constructed." Whereupon he rather scornfully asks, "Who would think of asserting that in the properties of brass and iron or steel we shall find the explanation of the construction of a watch?" Nobody; with this interrogatory Dr. Beale knocks over a man of straw set up with his own hands. What he calls "the material contention" is really that every phenomenon owes its existence to the properties of matter; but this contention his crucial instance does not meet, for denying that a watch owes its existence to "the properties of brass and iron or steel" is not denying that it owes its existence to material properties, acting under special conditions, in special combinations, according to special laws, and emerging into a special organism, with the capability of watch-making: he answers what is asserted by denying what is not asserted. The fallacy, however, may suggest the clew to a better comprehension of the reality. Why do
