147 
of Edinburgh, Session 1869 - 70 . 
Tlie cause of this change in Faculty-work was, in fact, the rise 
of different methods of philosophical inquiry named the reflective, 
which discarded all observation and experimental research what¬ 
ever. Sir William Hamilton explicitly taught that the only ex¬ 
ternal condition needed for philosophical inquiry is a language 
“ capable of embodying the abstractions of philosophy without 
figurative ambiguity,”—a condition not yet attained, however, nor 
likely to be. “With this one condition,” Sir William declares, 
“ all is given; the philosopher requires for his discoveries no pre¬ 
liminary preparations, no apparatus of instruments and materials 
. ... it is only necessary that the observer enter into his inner 
self [and here is truly a figurative ambiguity of language] to find 
there all he stands in need of.”* Hence the reading and writing 
of books, and discussions of opinions, are the proper results of 
reflective inquiry. It was to his extreme devotion to the literature 
of philosophy that was due that lamentable palsy of the sign- 
making organs, the right hand and speech-muscles, termed aphasia , 
with which he was afflicted, for these were overworked in the acqui¬ 
sition of that immense erudition which distinguished him. The 
locality of the brain-disorder in these cases is in the anterior lobes, 
more especially the posterior third of inferior frontal convolution. 
Although the principles of the reflective method there laid down 
by its greatest modern master exclude observation and experi¬ 
mental research, Sir William Hamilton did not neglect physio¬ 
logical inquiry. My own researches into the reflex and unconscious 
functions of the brain, made twenty-five years ago, were'rewarded by 
his highly valued approval and friendship, because he saw in them 
the physiological side of his doctrine of “latent” consciousness; 
but the kind of inquiry he followed was physiological in the re¬ 
stricted sense of a physiology of the human brain, and not in the 
wider sense of a science of nature. But I do not advocate this 
restricted method as the best or even a true method of philosophical 
inquiry, nor do I wish to defend the errors to which it leads. I 
speak only for my own method as just explained. 
Matters being thus, it interested me to read the manifesto of 
principles and methods which my reverend and respected colleague, 
* Lectures on Metaphysics, vol. i. p. 383. 
