There are several cheeses for which this honour is claimed.
What strikes me about this list is its apparent diversity - soft and hard, strong and mild. What is the set of purposes that all these cheeses (and so few others) satisfy?
But as you might already know, this is not a blog about cheese but about purpose. My son returned late from a party last night, ate a toasted cheese sandwich and went to bed. This morning he reported an unusual quantity of dreams, and we were minded of the old wives' tale about cheese causing dreaming.
So is that the purpose of cheese? Salvador Dali produced some interesting paintings after dreaming of Camembert. Or was it just that he produced paintings about dreams after eating Camembert? [Meg Nola, Martin Ries] Unfortunately I can find no clear evidence for the suggestion (which appears in a few random internet comments) that he ate cheese before bedtime deliberately to stimulate dreams. Wasn't that the Dream of the Rarebit Fiend?
A recent study has confirmed the effect of cheese on dreaming. Steve Jones blames Tyramine (found especially in Stilton). Apparently different types of cheese produce different types of dream: Sweet Dreams are made of Cheese (British Cheese Board, 25 September 2005. Also reported in Mail and Sky. See also discussion in the Museum of Hoaxes and The Virtual Stoa.)
Or maybe it was the party that prompted my son's dreams, nothing to do with cheese at all. I wonder if my son is up for a bit of scientific experimentation ...