You do, in the exact same way firsts physicians did. The simplest first steps to garner that understanding were made by Eratostenes, and you can read his method.

didiplaywell

How do we know if the earth is flat or round? A lot of pilots say it's flat. I have no way of knowing. 

DesertDave

alter_native

Have you ever completely changed your mind on something big?

Signal312

> I don't think there is one right way

It can be pretty irrelevant for miles, even entire lives. You can be *convinced* that a man dressed as godzilla is the all powerful god that governs what tone of green the grass will be. And you can go about your entire life with it without wrongly affecting anyone's life.

Now, if you are *convinced* that the earth is flat and demand planes to stop flying like if the earth is round, *there* we have a problem.

> I just like relating to all types of people and expanding my perspective.

As you said: "So, again, it's how we connect."