Only if we let the ends justify the means. If we consider them as ways to learn about the world, logos beats the other two hands down.
That being said, I am slowly turning into a Machiavellian pragmatist: what can I say that will get the results I want? Mayhap that would be the best approach to change peoples' minds. Some people would call it deceitfulness; others would call it diplomacy.
Ethos is an appeal to authority or credibility. Pathos is an appeal to emotions. Logos is an appeal to reason.
I think we overvalue logos.