380 Mr. T. V. Wollaston on the Tarphii. 



number of men and measure them (say by hundreds or thousands), 

 and wo can then prove, to an ocular demonstration, the precise limits 

 between which they have varied in their stature ; for this is a " truth 

 of sense." But is it, on that account, one jot more certain than the 

 other ? Most decidedly not. And hence we arrive at the convic- 

 tion that the limits are not the less real because (by the nature of 

 the case) we cannot prove them, and that to dispute their existence 

 merely on the latter account, so far from being " philosophical," is 

 simply foolish. If they are to be objected to at all, our philosophers 

 must entrench themselves on more logical ground than this. But 

 there is a point yet to be noted. A mathematician, in ascertaining 

 the limit of a " vai-iable," treats it as a single function. Not so, 

 however, the physiologist ; for his " variable " is an organism, 

 which itself consists of many variables. The " growth," to which 

 we have just alluded, is only one of them. But, nevertheless, pre- 

 cisely the same reasoning will apply to each one separately ; and after 

 having reasoned them out in a similar manner, if we add up the 

 several results we have arrived at, we may assert broadly, without 

 fear of refutation, that the same reason which assures us that the 

 growth of the human species is limited, assures us also that his other 

 functions have likewise their respective limits (even though we cannot 

 define them), and that, consequently, (to take no wider margin) he 

 neither sprang from an ape, nor will be developed into an angel. 



Now these considerations will illustrate our meaning (albeit perhaps 

 somewhat grotesquely) when we insist on the reality of limits, as an 

 abstract truth. And let it be well noted that the admission does not 

 imply any verdict against specific variation ; it merely affirms that 

 the limits of that variation are prescribed, and that it is illogical to 

 argue that they do not exist, because (in the nature of things) we 

 are of course unable to trace them rigidly out. No doubt in some 

 instances the range for permitted variation may be, as lately stated, 

 very great, whilst in others it may be reduced almost to zero — de- 

 pending, in every case (as practical naturalists are well aware) on 

 the inherent pliability of the particular species. But these are points 

 which, even allowing for our imperfect judgment, may usually be 

 determined approximately by patient observation ; and Ave should 

 remember that when we have done this we have done all that it is 

 possible to do with our limited faculties, — the approximate result 

 being, for us, to all intents and purposes, the actual one. 



In the above illustration, borrowed from the growth of the human 

 species, it is needless to remark that we might have reduced the 

 distance between the supposed limits very considerably, and yet 



