1885. | The Relations of Mind and Matter. 949 
Between the extreme states we have the condition of pleasure, in 
which the mind seems gently warmed, and of gloom or depres- 
sion, in which it seems similarly chilled.1 The reasoning power 
is most efficient in calm states, when the temperature is normal. 
Then consciousness is diffused and its vision extended. In the 
other conditions it becomes more concentrated, until, in extreme 
heat or chill, a single idea or feeling dominates the mind. 
We have not space here to consider the more aberrant condi- 
tions of mentality, such as somnambulism, hypnotism, insanity, 
&c., and the various strange phenomena which attend injury to 
the brain. None of them are incongruous with the idea that the 
mind is a distinct organism, and the brain its instrument of activ- 
ity. Nor can we consider the many interesting relations of 
thought to thought or memory to memory, and the interaction of 
memories which lie at the basis of the evolution of ideas. Many 
of these are highly interesting and peculiar, yet there is nothing 
_in them inconsistent with the hypothesis we have advanced. It 
will suffice to say that no thought ever calls up another unless 
they are directly or indirectly related, or associated in time or 
place of reception. It may be said, however, that our ideas differ 
i widely in their degree of fixity in the mind and influence over its 
movements. Below all, as the basis of the organism, lie a series 
of deeply-based hereditary conditions, gained during ages of 
mental development. These are very persistent, and strongly 
resist warping influences. And the effort to perform any action 
inconsistent with them is vigorously resisted, even though we 
may be very faintly conscious of the source of the resistance. 
The mental development obtained during youth is also deeply 
based, and actively resists the warping influence of later impres- 
sions. The later the impression in date of reception the less 
firmly does it seem implanted, as if these late impressions were 
but slight and superficial affections of the more deep-laid early 
Stages of development. 
1 “Tn certain animals there is occasionally a ae ‘wildness of joy,’ great inten- 
sity of mental excitement from pleasurable emotions. Thus Darwin speaks of the 
‘ madness of delight’ in a stickleback, meaning, no doubt, exhuberance of joy, or 
_ uncontrollable animal spirits.” Ibid, 11, 233- 
Thus strong pleasure seems to produce general activity of mind and body, w 
deep. grief or depression from any cause produces sluggishness and inactivity of con- 
Sciousness, just the effects which would naturally flow from states of heat or chill in 
a physical organism, 
