Critical rationalists hold that scientific theories, and any other claims to knowledge, can and should be rationally criticized, and (if they have empirical content) can and should be subjected to tests which may falsify them.
Thus claims to knowledge may be contrastively, normatively evaluated. They are either falsifiable and thus empirical (in a very broad sense), or not falsifiable and thus non-empirical. Those claims to knowledge that are potentially falsifiable can then be admitted to the empire.
In plain English: Being rational is one thing, but are you thinking critically as well? If you are, then you are open to the idea of being wrong, because it leads to a better society. People have killed and been killed over ideologies that were later proven to be invalid. Many were neither rational nor critical of their own ideas. Some were only one of these things.
So how about it? Before another law is passed, before another person dies or kills for the wrong reasons–let’s think critically and rationally about EVERYTHING. That means putting your party-specific biases aside.