Humans' decisions are affected by "counterfactual" futures all the time when planning, and so the counterfactuals have influence

Human decisions are affected by thoughts about counterfactuals. So the question is, what is the nature of the influence that the "content" or "object" of a thought, has on the thought?

I do not believe that when human beings try to think about possible worlds, that these possible worlds have any causal effect in any way on the course of the thinking. The thinking and the causes of the thinking are strictly internal to the "world" in which the thinking occurs. The thinking mind instead engages in an entirely speculative and inferential attempt to guess or feel out the structure of possibillity - but this feeling out does not in any way involve causal contact with other worlds or divergent futures. It is all about an interplay between internally generated partial representations, and a sense of what is possible, impossible, logically necessary, etc in an imagined scenario; but the "sensory input" to these judgments consists of the imagining of possibilities, not the possibilities themselves.