What is a symbol

C.G. Jung defines the symbol as the best possible explanation of facts that are so vast and so deeply felt that they can only be described through analogies with our physical world (Collected Works 6, pars. 814-29). Such words as life and death, love and marriage are symbols because they are much more than mere concepts; they don’t only signify, but they evoke feelings, focus and conetrate the mind in an analogical manner.
With examples from ancient Greece and modern authors (Ursula Le Guin, Terry Prachett) I try to make explain what symbols are about.