Ask whether you would rationally act on your maxim is such a world ?

In a world where everyone acted on the same maxim, it would depend on the specific maxim in question. If the maxim aligns with my values and beliefs, then I would likely rationally act on it. However, if the maxim goes against my principles or would harm others, then I would not rationally act on it. Ultimately, the rationality of my actions would depend on the ethical implications of the maxim in that world.