Sorry if I came across as criticizing a weak version of the rule. But I have had trouble trying to think of what a strong version might look like: "In most cases, if you don't like someone, then it just means you don't know them well enough" ? The assumption here seems to be that if you get to know someone well, then you will come to like them most of the time? I get that people are complicated but I don't think coming to understand a person more fully will necessarily lead to liking them more - but I suppose this depends on what type of person you are - someone who generally doesn't like people, or someone who is very picky etc, likely will not ever come to like most people even if they gain full knowledge of them, which makes the rule even more subjective.

On the other hand, some may argue that not liking someone means that you ought to study them more, which makes sense in the general sense of "you ought to know your enemy", but this seems incongruent with the original context of the quote.

I suppose I did oversimplify the rule in order to make it easier to apply, which reduces it to absurdity. But trying to find a way to make the rule work is also making my head hurt.

In any case I hereby apologize if I have broken any rules.

One of the most important things, in my experience, when in an adversarial relationship, is to understand, and, quite often, to respect my opponent. I need to understand why they are doing what they do, so I can make plans to counter them. Often, I can find ways to defuse the conflict, by negotiating compromises.

A pithy way to put it, is if you want to understand rats, talk to an exterminator.

which would make you not like him even more, and thus wanting to know him better :D