Read this online and for some strange reason posting it here came to mind...

It's plenty fun to have a little off-the-cuff back and forth. But
if you're going to get self-righteous, or engage someone who clearly
disagrees with you and isn't going to give much ground, then you need
to hold yourself to a standard.

Say, ok, this is what I think is true. If it is
true, then the evidence will meet this, this, and this criteria.
Here are some links to things that match that criteria. In light
of this, I think it's reasonable to say the evidence supports my
argument–so how can you not see the validity of what I'm saying?

Then,
you've done your work. The other person either has to find
something wrong with the evidence you provided, or come up with
something on his own. In any case, while I'm still no fan of
arrogance, you'll be on far firmer footing to advocate your point of
view from than if you just said "well it's obvious that blah blah blah,
and you're just not looking closely enough". That gets you
nowhere. That's what we call a cop-out.

If you ever find
yourself losing your temper, or getting indignant, then ask yourself
this: how much evidence have you actually provided, that the person
you're debating with can actually go and check for themselves?
How much of it is just you expecting them to take you at your
word? And if that's all you got, how on Earth can you think it
fair to expect people to take you seriously?

Just some food for thought for a select group of respected posters.

TS