Dreams are symbolic expressions of the unconscious (and of the total psyche). A phylogenetically older form of thought. The dream is a fact of objective nature and therefore not a disguise. (Sugar in the blood means sugar and nothing else.) It is its own interpretation and is only misunderstood when we don't fathom its symbols. The manifest aspect is the dream images themselves, and they contain the "latent" meaning. It's not what causes a dream, but it's purpose, that matters.