1884*] Latent Thought. 72 
doubtless the foundation of all these adaptations, it does not 
yet appear. That high light-intensities do not depress the 
decomposition of carbonic acid is certain ; that ordinary 
sunlight effects no increased combustion appears also cer- 
tain. . Other effects must therefore exist by which intense 
light is injurious to many plants. 
III. LATENT THOUGHT. 
By D. Y. Cliff. 
{jC? EMARKABLE incidences of parallelism in thoughts 
■jj-pV ar . e constantly occurring in every-day life, and in the 
wider field of human history, where whole races 
“think alike,” and often it is the civilised world. Is it not 
a wonder a man is never born who thinks totally different, 
not only in style, but in logical sequence, to his fellow-man ? 
Nor is this nonsense, for I believe it is J. S. Mill who has 
said it is conceivable that there may be a species in the solar 
system with whom two and two make five. 
It is worthy of notice, if we will think on the matter, how 
every thought we think is mentally expressed in our verna- 
cular. Unpremeditated sentences spring out of our minds 
without an effort, but they must have been arranged inter- 
nally before directing the vocal muscles. Is a thought 
spoken before it is considered, however swiftly ? 
I am inclined to think there is a continuous train of 
thoughts in our mind of which we are not aware, either of 
its existence or its laws, — a necessary result, so to speak, of 
the brain or nervous “ molecular motion ” or “ vibration,” 
and it is only when we require “ to language ” it that it is 
brought into activity. Surely mental activity must be con- 
stant, as we see with dreams : perhaps we are only aware of 
dreams in the interval between awaking and sleep. 
I have heard of missionaries who became so used to the 
barbarous tongue in which they taught that they came to 
“ think in it.” Is there latent thought ? This latent 
thought would naturally be hereditary in a family, a race, a 
nation, or even the human species, and would do away with 
