One predictable way I have seen many rationalists (including myself) deceive themselves is by flooding their working memory and confusing themselves. They do this via nitpicking, pursuing arguments and counter-arguments in a rabbit hole depth-first fashion and neglecting other shallower ones, using long and grammatically complex sentences, etc. There are many ways. All you have to do is to ensure that you max out your working memory, which then makes you less able to self-monitor for biases.

How do you counter this? Do note that arguments are not systematically distributed wrt. their complexity. So it's just best to stick to simple arguments which you can fully comprehend, and with some working memory capacity to spare.