Button T, The Limits of Realism, 2013, pp. 8-9:
For the correspondence theorist, true theories do not aim to copy the world, but aim only at some kind of structural similarity.
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The Correspondence Principle. 'Truth involves some sort of correspondence relation between words or thought-signs and external things and sets of things.'
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But perhaps even the correspondence theory of truth is too ambitious, since it insists that there must be a structural similarity between the subject/predicate distinction of some language and the object/property distinction in the world.
What does the author mean by structural similarity here?
I think I understand correspondence theory. According to correspondence theory, the word "apple" in the English language corresponds to the apple fruit that is mind-, language-, and theory-independent. However, I don't think there is any structural similarity between the word "apple" and the apple fruit. What does structural similarity even mean in this context?
For example, a cow and a horse are structurally similar. However, how can sound waves (words) be structurally similar to a physical substance (apple fruit)?