How do you know if something is true or not true?

To believe in something you have to have a point of beginning if noone is right or wrong.


Then how do we get people to do right or wrong.How do you know if something is true or not true?
From when I was younger in school I was taught the lesson on what is right and what is wrong. Facts are the only peices of information to have right and wrong. Opinions can not have a true or false answer for sure.





Example:


1+1= 2 - Right/True


George W. Bush is a horrible president- Undecidable (Though many believe it is true, it can not be scientifically proven.)





But I don't truely believe that. We also know that killing an innocent man is wrong. He know that Genocide is wrong. We know that peace is right.





What's right in your life can only be told from that little voice in your head and the heart you have.How do you know if something is true or not true?
That's two different questions.





True or untrue is one issue. It's harder to prove the truth than it is to dismiss an untruth; to prove a truth, you must either provide irrefutable positive evidence or else you must eliminate all other reasonable possibilities. To disprove an untruth, you need merely find inconsistencies, contradictions, absurdities, gross improbabilities, or the existence of an exculpatory truth.





Now, ';right and wrong'; is in the domain of ethics, not metaphysics like the ';true or untrure'; question. And how to get people to conform to ethical principles is yet another level of ethics. The answers for right or wrong are far less clear.
I don't really understand the question.
Philosophy has certain objective controls which test the truthfulness of propositions. There is the correspondence theory of truth (the adequation of a thing and the intellect) in which P is true iff P. Moreover, one can ascertain the possible truth conditions of a proposition by testing the coherence of a proposition. Is the proposition or judgment internally consistent. There are other controls for veracity, but these are two prominent ways of testing the truthfulness of propositions.
Only by testing something by mathematical equation can you prove truth. What is more true than 1 + 1 = 2 ?
The truth is actually very subjective. Some people only see one side of the situation, so that is the truth for them, but it may be untrue for others. It all depends on where you see it. Did he crash into her or the other way around? It all depends where you were standing at the time. That's why so many witness's accounts can be different, but all are right.
well, you can tell if people aren't telling the truth sometimes.


you can find out the hard way,


and when people are using sarcasm
i think u have to have a logical criteria for it
Run it through a truth table, look for the tautology: all TTTTTTTTTTTTs.