It's not assuredness, it's that a deduction is the same as getting a maths problem correct, only we are using language, that foggy problem!
If you calculate 5 x 5 and KNOW it's 25 do you doubt yourself, because people can't see it?
Now, I am not always correct, this I conceded, but I can tell you whether I am correct certainly, when I am.
There is a particular kind of arrogance that I only ever seem to find in Christians who are so self righteous that they are _sure_ they are correct.
The problem is these people are inevitably under educated and virtually without rational thought.
Yes, if you and everyone else agrees 5x5=25, then it's probably correct.
However, if you insist that it's 26, because you _KNOW_ it is, and the vast majority of people are telling you you are wrong, you need to re-evaluate the "skills" that you are using to come to your conclusion.
Religion is fine the same way philosophy or professional sports are fine. If you want to spend you time doing that, good for you. The problem is that more often than not, people who spend their time being "religious" aren't doing so for themselves.
If they were, we'd never hear about it.
No, they are doing so to shove it into everyone else's face, it breeds a kind of profound intolerance, a core hatred and a pillar of complete ignorance - and those three things are what drives these people.
If there were any truly religious people, they wouldn't be posting to a web forum such as this - trying to PROVE to us or SHOW OFF how spiritual they are.
Would the Dali Lama be posting to EVC? I think not.
So, any time we see someone with an icon proclaiming their faith, it's a fair bet that this person isn't worthy of the image they've chosen.