|Similarity: conformity of one or more - but not all - properties of two or more objects.|
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Equality/Experience/Perception/Cavell: it is not a matter to find a meaning of "equal".
E.g. same experience: two look at a mountain chain and hear a horn. Not the same: Your child is crying.
The question is a real question, but it is unanswerable when it relates to whether we have the same feelings.
Die Unheimlichkeit des Gewöhnlichen Frankfurt 2002