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Pre-suppositions of Judgment.
EPISTEMOLOGY AND LOGIC.
Then, again, you and I perceive objects and so we know them. But how do we know them ? Clearly because they make impressions on our brains through the senses and thus give rise to certain processes and states in our mind ; and the question is whether we have only mental processes and states and not the real objects with which they do not correspond at all like an image in a mirror and the real object imaged. This world of ours gives rise to perceptions with which they cannot be identified. The image of the book is evidently not the book itself. If you shut your eyes, the image of the book vanishes, but the book existing objectively in space does not. Supposing, again, that you go away to a certain distance from where the book lies and look back from there at it, surely the image of the book will be smaller and smaller as you go away from it farther and still farther and look back at it from time to time. Clearly you see the book as it does appear to you and not the book as it really is. And thus the whole thing grows at once perplexing and irritating ; and you are irresistibly led to the question-what
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