If you think about that for a moment, you should realize that if you accept it, you're going to have to suspend belief about a whole lot of things. This approach to disagreement leads to a significant amount of skepticism, though not, at least as far as I can see, the kind of sweeping philosophical skepticism that is intellectually crippling. We can still believe, for example, that a computer screen is in front of us, that Kennedy was assassinated in the sixties, that OJ was probably guilty (even if that belief isn't beyond all reasonable doubt) and that the gene is the unit of inheritance. But what should minimum wage be? What should be done about income inequality, anthropogenic global warming, and ISIS? Is Allah or Jesus God? These kinds of questions would seem to require the humble approach of agnosticism, and further argumentation, experimentation, and evidence. Sometimes, we are forced to act despite being agnostic, but notice that there's nothing wrong with taking a "best guess" when that's all that is available.
In part 4, I’ll apply this reasoning to a case of disagreement in the Cardiology community and explain how it is being addressed. Chime in now with your own disagreement and you just might find me addressing it in part 5, when I will consider some criticisms of approaching disagreement in the logical fashion I have been describing.