Rationality goes wrong when it's used to judge people rather than beliefs. Belief-judging rationality is logical contemplation of ideas to try and remove falsehoods and inconsistencies. Person-judging rationality is in practice emotionally based moral judgement, usually judging people as either rational or irrational so you can dismiss them. There's no such thing as an irrational person, only irrational beliefs, it's an important distinction. Any good rationalist should use two options, you believe you understand or believe you don't un... (read more)
While disagreements are often matters of miscommunication, mistakes are possible, especially for those who are not all knowing and perfect in their calculations.
Rationality goes wrong when it's used to judge people rather than beliefs. Belief-judging rationality is logical contemplation of ideas to try and remove falsehoods and inconsistencies. Person-judging rationality is in practice emotionally based moral judgement, usually judging people as either rational or irrational so you can dismiss them. There's no such thing as an irrational person, only irrational beliefs, it's an important distinction. Any good rationalist should use two options, you believe you understand or believe you don't un... (read more)