What a great question.  You probably have some idea of what the answer is, if you think about it.  If he is a dependable person who is capable of putting your needs first ,when you need to be first, and yet not ignore his own happiness; and if he is considerate more than selfish, he must be a good man.  When you talk does he listen and have a caring response?   When you are sick or tired does this guy stay home with you or make an excuse to go out with the guys because you need to rest and he might bother you?  How often during one week’s time does he call his mother, ex-girl friend, or his buddies, while he is out with you? Finally, does he ever reference the future by saying things like “next year at this time we will be in Italy” or” in two years we will have enough money to take that trip to China.”  If you don’t fight about money, and he keeps his promises, doesn’t mind your stuff all over his space, and always introduces you to everyone he knows, immediately upon seeing them; the chances are that you will get that commitment in a reasonable amount of time.