Determining Truth

I once had the opportunity of observing a trial. The trial was between two individuals who had gotten into a fight. According to the witnesses, there had been drinking involved, threats, and fists thrown. I had a chance to talk to the judge afterwards and what he said amazed me. He said that the human mind is unreliable. In his experience, witnesses to crimes frequently do not tell the truth. He came to this conclusion because witnesses to the same incident will often contradict each other. He also said that these errors are generally not made on purpose. The witnesses truly believe what they are telling the judge is the truth but perspective, emotion, faulty memory, and human frailty cause their view on reality to be skewed. It was his job to sift through the testimony and try and determine what the actual truth was.
We human beings decide on what is truth by receiving input from our senses and using our brains to come to logical conclusions. Let's suppose that a adult was knocked on the head and lost all her/his memory so that (s)he had to start determining truth all over again. (S)He picks up a stone and lets go of it and notices that it falls down to the ground. His/Her mind creates a theory that things fall toward the ground. (S)He tries it again and the same thing happens. The theory becomes more solid in her/his mind. After numerous tries, (s)he decides that the truth of the matter is that when something is dropped, it falls toward the ground.
Science decides on truth in much the same way except that there are no facts in science. To be an absolute fact, there has to be zero chance for the theory to be broken. The only way to know for absolute certain that the stone will fall toward the ground every time would be to perform this experiment every time possible. Since we cannot perform experiments infinity times, we cannot say with absolute certainty that it is truth. We call things "facts" when there is an extremely high likelihood of it being true. The only certainty is a reasonable probability in the scientific world. Thus it all comes down to percentages. Determining truth is like a big poker game. If there are extremely high odds for a theory to be true, it is considered truth. It is our job then to calculate the probabilities, taking into account that our senses are fallible and the truth may have to be adjusted if we receive new input.