> In more detail, we know that it’s possible with our laws of physics to build a self-replicating machine: say, DNA or RNA and their associated paraphernalia. We also know that tiny molecules like H2O and CO2 are not self-replicating. But we don’t know how small the smallest self-replicating molecule can be—and that’s an issue that influences whether we should expect to find ourselves alone in the universe or find it teeming with life.
DNA and RNA typically isn't self-replicating. As indicated in this very quote is takes a machine to do so.
In a world with 'volcanoes' that emit pure hydrogen gas and pure oxygen gas (not from the same 'volcano', H2O could indeed be self-replicating by generating a greenhouse effect raising the temperature to the autoignition point of hydrogen gas (535°C according to Wikipedia).
These are nitpicks, though. I get the general point.
DNA and RNA typically isn't self-replicating. As indicated in this very quote is takes a machine to do so.
In a world with 'volcanoes' that emit pure hydrogen gas and pure oxygen gas (not from the same 'volcano', H2O could indeed be self-replicating by generating a greenhouse effect raising the temperature to the autoignition point of hydrogen gas (535°C according to Wikipedia).
These are nitpicks, though. I get the general point.