The first of the six leads is for people to ask themselves: what do you really believe anyway?
It's really tempting to think that things are either for you or against you. They're
either good or they're bad. They're black and white. Tim Minchin has a really nice example of this.
"The Fence" is the name of the song, and picturing the world as either black or white,
for me or against me, instead of having shades of gray in between. The same thing happens with opinion change.
That's right. If an observation is surprising enough, it allows you to think about, to understand
what you really believe. What's really important to you? Now this is actually what a lot of
university courses are trying to achieve.
The second of the six leads is: how well based is the opinion that you already hold?
Now sometimes support for an opinion can't always be based on formal data or experiments.
The data may just not be available, so personal experience might be the only thing we have to go on.
That's exactly right. We obviously are looking through the lens of this personal experience
that has been heavily shaped by your interpretation, as we've just seen throughout the episode.
The way that we see the world may not be the same way that other people see the world,
and so that personal experience might be somehow tainted in a particular way.
That leads us to the third lead, which is: how good is the evidence? Is it based on experiments?
Is it based on that personal experience? How good are the data? How good is that evidence?
What most people do when they're faced with surprising evidence, like the large class-small
class, is they have this new evidence, and then they just disregard it. They just ignore it from that point on.
Or look for flaws in the evidence or the data. But, even if you do find a flaw, you have
to ask yourself: is that flaw so terrible that you can legitimately disregard this new
piece of evidence that you've been given? Is the data so bad that you can just ignore it?
Like in the large class-small class example, are the experiments that have been done just
so terrible that you can ignore them and continue to believe what you believe?
That leads us to the fourth lead in opinion change, which is: does the evidence really
contradict what you already believe? Is there a way of reframing the issue, of stating the
evidence in a way that allows you to use this new information, this new evidence, rather
than just rejecting it outright?
Absolutely. Given the problem that's in front of you, given the evidence that somebody's
presented, if that's not enough for you to change your mind, change your opinion, then
what would be enough? If I've just presented evidence or if I've just received evidence
that's somehow flawed or somehow insufficient, you need to ask yourself: if that's not enough,
what would be enough?
Yes, and you need to—if you can't find any evidence, if you can't think of something
that would change your mind, then it's really time to be cautious there about the basis of that belief.
Now that leads us to the sixth lead in opinion change, which is: is it worth finding out
about, or is just a case of why not? Why don't I just continue to believe this stuff? What's
the cost? Can I just persist in this belief? For example, "Should I just take the pill?
It doesn't cost much, and it doesn't taste bad, so why not stick with it?"
That's right. Going back to Jane's case, if she just took the vial of water and she felt
better, it's water, right? It was cheap. It didn't taste bad. She took it, she got better.
So why just not persist in that belief? That one's tricky. I mean, yes, but, we need a
caveat on that sixth lead where people can really use that one almost as a get-out-of-jail-free
card and just say, "Well, the cost is low, and therefore it really doesn't require me
to figure out what I actually believe about it." So I'd be cautious with that one, but,
yes, if the cost is extremely low and the payoff is high, yes, why not? Just go with it.
These six leads are going to become extremely important. Now we're dealing with benign examples
at the moment, but we're going to be moving into things like ESP, paranormal belief, applied
claims, health claims, where these issues, these opinions that people have might not
be so easily dismissible. I think having these six leads is going to be really useful when
people start examining their own opinions, and examining the opinions of other people.
If you want to change someone else's mind or their own mind, then it's really worth
considering these and keeping these in their toolbox.
I've asked the MythBusters exactly about this issue of opinion change, both the opinions
that they hold or the myths that they test, as well as other people's, the viewer's opinions
that they have. Here's what they had to say.