You may or may not realize it when it approaches, but its impact is all the same and the choice which it presents you with is always obvious. Based upon the choice you make in this moment, whether it is moral or ethical, personal or public, virtuous or sinful, it will stay with you. It will restate itself as a defining factor of your personality until the next moment you have to redefine yourself. The most important difference between a moment of definition and a turning point in life is that there is always a choice in these moments and it is always dependent upon you, and only you, to make the decision. An interesting side note, just because these moments are always obvious does not mean people never choose to ignore them. This is a tell-tale sign of a weak character or poorly tested morals. As Chuck Palahniuk said in Fight Club, would you rather be ignored entirely or be famous for your evil?