Your life is literally made up of the things you pay attention to. If those are happy things, you will probably be more happy than not, and vice-versa. Money gives you a choice about what to pay attention to. If you are in a survival or starvation situation, you will be forced to pay attention to surviving / eating. Not having a choice about what you can pay attention to means your life is defined by outside forces. If these align with what you like, you can be happy in those situations; but if not, you will struggle.