It rather annoys me to be told that there is anything novel in my three categories; for if they have not, however confusedly, been recognized by men since men began to think, that condemns them at once. To make them as distinct as it is in their nature to be is, however, no small task. I do not suppose they are so in my own mind; and evidently, it is not in their nature to be sharp as ordinary concepts. But I am going to try to make here a brief statement that, I think, will do something for them.
By the phenomenon I mean whatever is before our minds in any sense. The three categories are supposed to be the three kinds of elements that attentive perception can make out in the phenomenon.
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