Strong personal beliefs are not knowing.
How do you know that? Knowledge is defined by Webster's as...
facts, information, and skills acquired by a person through experience or education; the theoretical or practical understanding of a subject.
Knowledge is acquired by an adversarial process. As Walt stated...there is God or there isn't. It is foolish to state that there is no God when no one can possibly demonstrate this. There is climate change [global warming] or there isn't. It is adversely argued that while there may be climate change, it is not caused by people. On the other hand, it can be argued that CFCs, coal, fossil fuel and other pollutants could be doing the atmosphere no benefit at all.
The Warren Commission Report approached the JFK assassination from only one direction. There was no consideration of any conclusion other than Oswald was the sole assassin. It was a blatant choice..extremely obvious and it remains so. Reasonable doubt did not take a back seat in the so called investigation ...it was not even along for the ride. For the authorities to not arrive at the conclusion that it ultimately did [right or wrong] was just simply unacceptable.