No external pushing is needed for a bike to roll down hill. Contrast this with a endergonic reaction which is sorta like riding a bike up a hill. Riding a bike up a hill takes ALOT of energy from the person riding the bike.
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.