That’s a given. She can easily tell that Jason believes that if his poems don’t contain heaps of beauty, then they aren’t exceptional poems. She however, knows this notion is false. You should add a bit of beauty to a poem, but not too much, or the poem will be spoiled, much like salt when added to a certain food dish where salt is appropriate. When Madame Crommelynck brings up the examples of natural beauty, and Jason brings up the artificial beauty of the vase, Madame Crommelynck scoffs and shows that, while the vase may look nice, is bound to all vases’ fates: shattering to pieces, losing its beauty. This shows that artificial beauty is bound to disappear, but natural beauty will live on