Question

Have a good week!
What is the difference between Frege's distinction between “sense” and “reference,” where the reference is the object the word points to, while the sense is the conceptual content of the notion (the famous example is that while a unicorn has no reference because it does not exist, its sense is the set of properties we attribute in our thought—that is, in our language—to that concept), and de Saussure's distinction between the “signifier” and the “signified,” where the signified is the meaning the word points to (the referent), and the signifier is the meaning we have in our minds for it?
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