362 FOOT-NOTES TO EVOLUTION. 
may mean instant cessation of these processes. The 
balance advises us as to all this. All these instruments 
of precision belong to science. They are examples 
taken from thousands of the methods of “ organized 
common sense.” By means of common sense, organized 
and unorganized, all creatures that can move are en- 
abled to move safely. The security of human life in its 
relations to environment is a sufficient answer to the 
“ philosophic doubt ” of Berkeley and Balfour as to the 
existence of external Nature; for if all phenomena were 
within the mind, no one of them could be more dangerous 
than another. A dream of murder is no more danger- 
ous than a dream of a “ pink tea,” so long as its action 
is confined to the limits of the dream. But the relation 
of life to environment is inseparable and inexorable. 
Cause and effect are perfectly linked. This is a world 
of absolute verity, and its demand is absolute obedi- 
ence. Life without concessions or conditions is the 
philosopher’s dream. 
What we know as pain is the necessary danger sig- 
nal. Without pain, life conditioned by environment 
would be impossible. Organic beings 
need such stimulus to veracity. Those 
dangers which are painless are the hard- 
est to avoid; the diseases which are painless are the 
most difficult to cure. 
In this relation must science recognise the value of 
ideals? The ideal in the mind tends always to go over 
into action. The noble ideal discloses 
itself in a noble life. It is part of the 
wisdom of each generation, its science as well as its reli- 
gion, to form the ideals of the next. History is fore- 
shadowed in these ideals before it is enacted on the 
stage of life. An ideal is not a dream. A dream is 
fleeting. An ideal has the w// behind it. Its essential 
Meaning of 
pain. 
Value of ideals. 
