…when the mind declares that what it sees now, or remembers to have seen yesterday, is like what it remembers to have seen last week, the likeness, which though accompanied like all mental processes with a peculiar and characteristic sensation, is mainly a fact, a mental fact, and the sensation of it is of no consequence except as an advertisement of that fact. That fact is that by virtue of the occult working of the depths within us, those two feelings coalesce into one notion. For the sake of calling this by a familiar name, I call this association by similarity. But the ideas united by virtue of an occult inward power, are not always regarded as similar.
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