Clearly there is no limit to the web of meaning spun by 'free association' , or to put it the other way round, in Freud's language, 'the degree of condensation is - strictly speaking - indeterminable'. But Freud found that not only did each element of a manifest dream tend to lead to some latent common denominator; but a single latent thought was also prone to be represented by several manifest elements - an interrelationship he referred to as 'over-determination'. Freud attempted to unravel the principles or 'grammar' which governed the transformation of underlying thoughts into a remembered dream, a process which he designated 'dream work'. As well as 'condensation' and 'over-determination', he invoked 'displacement', bu which he meant the shift in value that enabled elements in the manifest dream to seem important when they appeared peripheral to the underlying content; and 'symbolisation', the process whereby images of one thing came to suggest or stand for another. Perhaps the most vulgar misconception concerning The Interpretation of Dream is that in it Freud 'invented' sexual symbolism - the representation of male sex organs by objects such as cigars and umbrellas or wild beasts, female sex organs bu round or hollow containers, flowers, fruit, etc. But witness for example the 'Song of Songs': BRIDE: Sweet dove, already you are in the cleft of my rock, enclosed in my cavern. Look up, let me see your handsome face. Speak to me, let me hear your sweet voice. GROOM: Let us fetch us little foxes, little foxes that plunder the vineyards; for our vineyards are full of grapes. BRIDE: My beloved is mine, as I am his, He browses among my lilies. Until the day dawns and the shadows fade, turn again to me, my beloved! Be like a wild goat or a hart grazing on the hills of Boter. Such symbolism, as Freud points out, has been prevalent in folklore, myths, legends, idiomatic phrases, proverbs, and witticisms since time immemorial. Freud merely expanded the list to include dreams. In fact, the general currency of sexual symbolism presented a problem for the main thesis of the book, since Freud found that the meaning of a symbol could not ve derived (as his method demanded) from the idiosyncratic associations of the dreamer. His recognition of the role of symbolism in dreams forced him to modify the method to include direct interpretations based on the analyst's knowledge of common usage. All the tropes and conceits familiar to the literary imagination, Freud attributes to the language of dreams, But he was certainly not unique among his generation in doing so. The Scottish writer Robert Louis Stevenson, also fascinated bu the anatomy of dreams, expressed a similar idea several years earlier in a letter to his friend Own Wister: '...dreams are merely novels, they are made with every sort of literary trick' a word stands for a year, if it is the right word, equally with the reader and the dreamer.'