585 
the scene, either going back to Wittenberg or joining the 
forces of Fortinbras, and from the distance frustrating 
with his vacillating policy the action of the friends who 
were entrusted with the duty of discovering the guilt of 
the king and avenging the death of Hamlet’s father. Nay, 
we might go even further than this. A play might be 
written, in which the whole plot turned upon the probable 
appearance of some quite supposititious character, and the 
dénouement of the play might consist in emancipation from 
a stupendous delusion. 
Something very much like this must one day take place 
in the scientific world, if the opinions expressed in previous 
pages should ever prevail ; and if arguments, better than I 
have been able to urge, should be adduced. 
This audacious assumption suggests a difficulty at the 
outset. “ How is it possible,” it might be asked, “ that 
such an error could have prevailed ? Is it probable that 
the greatest scientific thinkers have been labouring under 
a delusion ? ” There are many reasons, it seems to me, 
to render such a phenomenon possible. First of all we 
must remember that there was a time when the contro 
versy lay between Fixity of Species and Organic Evolu 
tion by means of Natural Selection. Hence arguments 
for the fact of Organic Evolution and arguments for the 
process of Natural Selection, were treated as identical ; 
nay, the arguments for Organic Evolution were quoted in 
confirmation of the hypothesis of Natural Selection. In 
this way Natural Selection and Organic Evolution became 
almost convertible terms. 
The second reason why this theory prevailed, arose from 
the fact that it offered an explanation which was easily 
intelligible, which could be expressed in epigrammatic 
phrases, which seized on the popular imagination, which 
became familiar in our mouths as household words ; the