Memes

It's a valid point. But if you want to juge the ideas of anyone I think you also need to educate yourself to a degree.

I do think discussion/debate are a good way to learn though. Although a good debate must be anchored in reality, established knowledge and studies...

In the end I think it comes to what are you gonna trust or challenge. In learning I don't think you can only rely on one, you need a healthy balance.

(I'd say the more you know the easier it is to challenge more often. A new student might trust his teacher often while researchers might always challenge their peers.)

And I don't think that apply only to economics or politics, although entertainments might be taken less seriously.

Alternatively I believe in politics there is also a part that's subjective, depending on your values and culture.