130 Luck, or Cunning ? 
other, then the method of procedure observable in the 
evolution of the organs whose history is within our ken 
should throw light upon the evolution of that whose history 
goes back into so dim a past that we can only know it by 
way of inference. In the absence of any show of reason to 
the contrary we should argue from the known to the un- 
known, and presume that even as our non-bodily organs 
originated and were developed through gradual accumula- 
tion of design, effort, and contrivance guided by experience, 
so also must our bodily organs have been, in spite of 
the fact that the contrivance has been, as it were, de- 
nuded of external evidences in the course of long time. 
This at least is the most obvious inference to draw; the 
burden of proof should rest not with those who uphold 
function as the most important means of organic modifica- 
tion, but with those who impugn it ; it is hardly necessary, 
however, to say that Mr. Darwin never attempted to 
impugn by way of argument the conclusions either of his 
grandfather or of Lamarck. He waved them both aside in 
one or two short semi-contemptuous sentences, and said no 
more about them—not, at least, until late in life he wrote 
his ‘‘ Erasmus Darwin,” and even then his remarks were 
purely biographical ; he did not say one syllable by way of 
refutation, or even of explanation. 
I am free to confess that, overwhelming as is the evidence 
brought forward by Mr. Spencer in the articles already 
referred to, as showing that accidental variations, unguided 
by the helm of any main general principle which should 
as it were keep their heads straight, could never accumulate 
with the results supposed by Mr. Darwin; and over- 
whelming, again, as is the consideration that Mr. Spencer's 
most crushing argument was allowed by Mr. Darwin to go 
without reply, still the considerations arising from the 
discoveries of the last forty years or so in connection with 
protoplasm, seem to me almost more overwhelming still. 
This evidence proceeds on different lines from that adduced 
