"What does life do then? ...it seems reasonable that the earliest forms of life were ic... [i.e.,] they grew from gases... found in normal geological environments through an energy flux which is equivalent to cells which we see today, which is to say, what all life does today. There's a very simple phrase from Mike Russell... "hydrogenate CO2"... [i.e.,] add onto to make organic molecules. That is the structure of in cells, and different cells can get hydrogen from all kinds places. They can strip it out of water. They can get it from , but it also comes bubbling out of the ground as hydrogen gas, and that seems to be the simplest form of life imaginable as... life on earth. It's reacting hydrogen and CO2, and they don't react easily. The way that cells make them react... is to effectively use an electrical charge on a ... [T]here are environments like deep sea s that provide... for free with an equivalent electrical charge across a barrier, and I think... that's the way to see the question."