The real solution is a multi-candidate system and then proportional representation. The radicals would never get in then because there isn’t actually that many people who support them, but when there’s only two options (or effectively only two options such as in the UK) you have to pick one or the other, or not vote. So normal people end up voting for insane mad man who shouldn’t be in charge of a light switch, simply because there’s no better option.
The real solution is a multi-candidate system and then proportional representation. The radicals would never get in then because there isn’t actually that many people who support them, but when there’s only two options (or effectively only two options such as in the UK) you have to pick one or the other, or not vote. So normal people end up voting for insane mad man who shouldn’t be in charge of a light switch, simply because there’s no better option.