aside from the above post ill add the following.
Imagine your in a completely empty, totally dark 747 hangar.
I have set a bottle cap somewhere on the floor inside this hangar, and the bottle cap has been painted to blend in with the floor's color.
you can look for it one of two ways.
either
1. I can turn the hangar lights on
or
2. I can give you a small flash light which you can turn on and off for a few seconds at a time and it can only be shined directly in front of you.
which way would you choose?
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