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In his Book II Locke categorizes ideas into four groups
Ideas we get form a single sense. For example, sight or taste
Ideas we form from more than a single sense. For example, shape and sizes
ideas that emerge from reflections
ideas emergent from a combination of sense and reflection. For example pain , pleasure, unity and existence.
our idea of solidity is secondary quality, as it carries the power of that object to produce an idea of that quality in our minds. Thus, it can be separated from the mind. If solidity as a value does not exist as a value in a society we can't recognize it.
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