You start walking back to your car. You suspect that you aren't going to make it. Now does it make you happier to follow up on that thought and figure out the rate you are losing blood...
In the long run, and on average, yes. There are several courses of action open to me, such as "give up", "keep walking", "attempt to make a tourniquet", etc. Once I know the rate of the blood loss, I can determine which of these actions is most likely to be optimal. You say that "you suspect that you aren't going to make it", but I can't make an informed decision -- f.ex., whether to spend valuable time on making this tourniquet, or to instead invest this time into walking -- based on suspicion alone.
I sympathize somewhat with your argument as it applies to religion, but this example you brought up is not analogous.
You can't know in advance what beliefs you hold are false, however you can know which ones make you happy and don't get in the way of your life.
Perhaps not "in advance", but there are many beliefs that can be tested (though not all beliefs can be). To use a trivial example, believing that a lost Nigerian prince can transfer a million dollars to your bank account in exchange for a small fee might make you happy. However, should you act on this belief, you would very likely end up a lot less happy. Testing the belief will allow you to make an informed decision, and thus end up happier in the long run.
But even if the sun was about to go nova...
This is an off-topic nitpick, but the sun is incredibly unlikely to go nova; it will die in a different way.
[Note: Skip stuff in brackets if religious talk annoys or offends you]
(Why does everyone assume that this has to do with religion? If I was asking this about religion wouldn't that already signify that I didn't believe, I just wanted to? My belief comes from actual events that I have witnessed, and tested, and been unable to falsify. )
The example with the bleeding out was sort of a personal one because it happened to me. I cut my foot with an axe. I was far from help, and a helicopter wouldn't pick me up for another 4 hours. If I had been off to the side b...
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A list of some posts that are pretty awesome
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