Hi skygazer,
Okay, so you are a right-hand thumb over left-hand thumb person, huh? This suggests that you are a mind-over-heart person. You see, nature played an interesting trick on us. You are familiar with some brain mechanics, right? How the brain is split into 2 hemispheres, the left and the right hemispheres? Basically, there is this cross connection with the body and the mind. Being a right-hand thumb over a left hand thumb person suggests that your left side of the brain is more dominant. The left side of the brain deals with things the way they are-with reality (facts). When left brain people are affected by the environment, they usually adjust to it. Not so with right brain people. They try to change the environment. Left brain people want to know the rules and follow them. In fact, if there are no rules for situations, they will probably make up rules to follow. Anyway having said all these, left brain people would tend to be deontologists. Deontological moral systems are characterized primarily by a focus upon adherence to independent moral rules or duties. Thus, in order to make the correct moral choices, we simply have to understand what our moral duties are and what correct rules exist which regulate those duties. That is where Kant's Categorical Imperative comes in, in essence a standard or criteria is set. Thus, when we follow our moral duty, we are then behaving morally. Which kind of makes sense in your case because you probably felt that you are bound by your duty of promise to your friend to give the money to the manager of the Ginebra San Miguel team as he requested.
Looking at the opposite. For left-hand thumb over right-hand thumb people, this suggests that they are heart-over-mind persons. In the right side of the brain, this is where creativity and emotions are processed. Thus, if a person is a left hand thumb-over right hand thumb person, the right side of the brain is more dominant. In such a case, the person probably has a tendency to be emotional and in philosophical terms, most likely a teleologist. Teleological moral systems are characterized primarily by a focus on the consequences which an action might have. Thus, for teleologists, as long as the consequence of an action is favorable or good, then the action can be deemed as morally right. This is demonstrated by how one would support (ethical/situational) relativism or the notion that sometimes "the end can justify the means".
This is not to say that all of us, whether right hand thumb over left hand thumb (or vice versa) person does not have the characteristics of the other type. The ideal case, of course, would have a balance of the two characteristics. But in most cases, there’s always a dominant trait that comes out.
Going back to teleology and deontology, to simplify the comparison:
Teleology = What you achieve from your action determines the moral status of an action.
Deontology = What you do in your action, the nature of the action itself, determines the moral status.
Interesting, huh?