 In “Humean Supervenience Debugged”, Lewis notes how to extend this theory to indeterministic worlds. Some laws don’t say what will happen, but what will have a chance of happening. If the chances of events could be determined antecedently to the laws being determined, we could let facts about chances be treated more or less like any other fact for the purposes of our ‘competition’. But, as we’ll see, Lewis doesn’t think the prospects for doing this are very promising. So instead he aims to reduce laws and chances simultaneously to distributions of properties.