vil PREFACE 
ment I did not fail to indicate its weak points. I 
have never seen any reason for departing from the 
position which I took up in these two essays; and 
the assertion which I sometimes meet with nowa- 
days, that I have “recanted” or changed my 
opinions about Mr. Darwin's views, is quite unin- 
_ telligible to me. 
As I have said in the seventh essay, the fact of 
\ paleontology ; and{I remain of the opinion ex- 
| pressed inthe secon 
evolution is to my (ri sufficiently evidenced by — 
that until selective breeding 
is definitely proved to give rise to varieties infertile 
with one another, the logical foundation of the 
theory of natural selection is incomplete. We still 
remain very much inthe dark about the causes of 
variation; the apparent inheritance of acquired 
characters in some cases; and the struggle for 
existence within the organism, which probably 
lies at the bottom of both of these phenomena. 
Some apology is due to the reader for the repro- 
duction of the “Lectures to Working Men” in 
their original state. They were taken down in 
shorthand by Mr. J. Aldous Mays, who requested 
me to allow him to print them. I was very much 
pressed with work at the time ; and, asI could not 
revise the reports, which I imagined, moreover, 
would be of little or no interest to any but my 
auditors, I stipulated that a notice should be pre- 
fixed to that effect. This was done ; but it did not 
