The poem is a father defining for his son the qualities of a good man. he is setting the parameters or boundaries for his son and giving him a goal to achieve. The poem deals with life's challenges and hw to deal with them.
Stanza one deals with being confident about the decisions you make and taking responsibility for those decisions. If others, who cannot take that responsibility for themselves, react negatively, you will be patient with them and not reduce yourself to their level by telling lies or dealing in hate. However, don't ever think you are above anyone else.
Stanza two states that it is good to dream, but don't let your dreams control your life. It is good to think, but those thoughts need to be put into action. You will experience both triumph and disaster in your life. Don't take them too seriously because they are not the substance of life, they are the extremes. If you hear things you said misused or things you have done destroyed, you need to be able to pick yourself up and rebuild them with everything you have left in you.
Stanza three counsels not to be afraid to take risks and possible lose everything. If you do lose everything, don't talk about it, just start all over again at the beginning. When you have pushed yourself to your limit and you are tired and exhausted, use your mind and your will to move yourself forward. Push through it.
Stanza four deals with a person's reaction to others. You need to be able to talk to a large group of people and not let them influence your belief in what is right, wrong, moral, or immoral. You need to be able to walk beside men of power and influence and yet not lose touch with the common man and his needs. You need to know yourself and your beliefs so well that neither your friends nor your enemies can hurt you because you know who you are and what you stand for. People can depend on you, but don't let others become too dependent on you. It is important that you live every single minute of every single day of your life to the fullest. If you do these things, then the world is yours, and you will be a good man.