This seems to be somewhat more than faith to me. Faith of itself doesn't prohibit the chance of falsification. For instance, I have faith that my dentist is competent, but she could easily demonstrate to me that she's not. My faith in her competence is demonstrated though, when I let her put hardware in my mouth.
Faith needs to be a strong enough belief for us to commit action to it (otherwise it's merely opinion), but it needn't be so strong as to deny falsifiability. That seems to be some stronger form but I don't know what an appropriate name is.
Actually, faith, to me, does deny falsifiability. Usually, shaking someone's faith has adverse effects on identity and - possibly - self-esteem. What you're talking about here, I'd call trust (and the stronger form you can't name I'd call faith), which merely has adverse effects on the relation between truster and trustee.
If you have faith in something and it lets you down, you'll make excuses, because admitting defeat is hurting
yourself.
Anyway, scientists often exhibit faith, but when they start ignoring opportunities to check falsification then they stop doing science.
It is possible to set up theories in a way that the opportunities to check falsification don't arrive in the first place. This is was Popper was addressing, mostly, with his claim that falsifiability be a necessary precondition for science. He said such theories employ "immunisation tactics"; he levied such charges especially against Freudian and Marxist theories (see another recent thread).
Basically, without falsifiability, there's no peer review - a key concept for science.
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Here's a bit of context for Popper's falsification statements:
Popper has a hierarchy of theories:
The wider the application of a theory, the better it is.
"John Smith from across the street has blue eyes," is a very limited theory.
"All people called John Smith have blue eyes," is a better theory, as it applies to more people, and is - thus - a better theory.
Compare this to:
Hyp1: All crows are black.
Hyp2: Some crows are not black.
Popper would say that science should strive towards Hyp1 (which, I think, shows his positivist bias quite well).
Now, let's assume both hypotheses are flase. Look at how to falsify these hypotheses:
Hyp1: Find a crow that is not black. As soon as you find one, Hyp1 is false.
Hyp2: Look at all crows and show that they are all black. Notice how verification is a lot easier, here?
There's a problem with countering Popper by citing type two examples: you're building a straw man. Popper never said this. To Popper "There is water on Mars," would not have been a hypothesis; it would be something to check to verify/falsify a hypothesis.
If your hypothesis is based on an induction that suggests there is water on Mars and you do find there's water on Mars, this does not yet validate your induction. It merely states there's water on Mars, as you have expected. Your reasons for said expectations might be mistaken (e.g. because of hidden variables).
What Popper considers a good hypothesis in the scientific sense is not arbitrary. "This horse will win the race," is not a scientific hypothesis; it's a specific prediction. There's a definite moment of truth that just doesn't exist for a statement such as "All crows are black." It's a continuum. "There's water on Mars," is somewhere inbetween "All crows are black," and "This horse will win the race." There's a inverse proportional relationship between specificity and verifiability. Highly specific claims are easy to verify, but - scientifically - they're not very useful. Highly generalised claims are very hard - if not impossible - to verify, but scientifically they're quite useful. Falsifiability gives you a handle on the problem: it generally produces relevant facts that are easier to check for.
I disagree with Popper mostly on his positivism (from a perspective of social-epistemological relativism, I think, but I haven't come to a clear conclusion on that point), but once I accept that, his demand for "falsification" is - I think - valid. You
need to open yourself up to the risk of "getting it wrong". If you don't, you get stuck in a non-scientific, narcissitic loop.
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As for "not being able to falsify God" = "God is a viable theory": that's not true. You fail to falsify God because there is no condition under which you could say that God doesn't exist (in an empirical context). God would have to be introduced into science as an axiomatic assumption, not as a hypothesis. (IMO, God is too unspecific to even make for a good axiomatic assumption, but this is besides the point, here.)
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So what about "many worlds theory" vs. "Copenhagen Interpretation" in quantum theory? Does it even make a difference which one you chose? I'm honestly curious; my impression is that the discussions around this involve more faith (about how to make sense of strange science) rather than science. I notice "many worlds" is more popular in quantum computing - which may be a result of the mindset of the programmers.
I don't really understand quantum theory, so if anyone does: are there empirically specifiable differences? Or, differently put, what empirical circumstances could be used to falsify either hypothesis?