Sentence:  The "pineal gland," according to this view, though, as need hardly be said, no "seat of the soul," would nevertheless be the original single organ for conveying to the brute soul of our remote ancestors those luminous impressions which are the most potent agents in educating animal <WSD>consentience</WSD>. 
Meaning of the word marked with <WSD> tags:  An imperfect form of consciousness, that of animals or primitive humans.