Gulliamo said:
It goes something like this...
Step 1 Receive the Mission
Step 2 Analyze the mission
Step 3 Analyze assets
Step 4 Gather intelligence
Step 5 Develop courses of action
Step 6 Analyze Courses of Action
Step 7 Develop the plan
Step 8 Develop a contingent plan
Step 9 Make the decision
While I agree that is a good decision making process in general, I don't feel it completely answers the OP. (Though the OP is not mine, so whether that is helpful to jay is his *ahem* decision.) It seems to me the "tough" decisions are the ones where you've followed steps 1-6, but the course isn't clear. You've weighed the variables, thought about your overarching goals, but the final answer isn't available in some neat package.
To take your later college major example. Say my overarching goal is to make gobs of dosh. Well, Philosophy's right out the door, along with some others, but the field is still pretty wide. To arbitrarily narrow the field to two, let's say Law or Medicine.
Either will make me some fairly serious bank if I follow through, but which am I more interested in? Which am I more suited for? What about free time? When will I be able to retire? You get the idea.
All these questions, and more, can be researched according to the typical decision-making formula, but only up to a point. The future is too murky, too probablistic, too chaotic to make this decision with 100% confidence that it is the right one.
Any decision making faculty cannot be rules all the way down. At some point, as evildave said above, one just has to MAKE IT. Eventually, you have to execute, because you never have all the facts.
I happen to like TM's suggestion about the coin flips, but for a slightly different reason than he stated. I don't think it's so much that it shows us what we
really want. It shows us what desire is currently in the driver's seat of the useful fiction of the self. It seems to me short-term desires would overrule long-term goals more often than not in this method. (Well, there's this really hot chick who's taking Pre-Law, so screw Medicine.) I think the use of the coin is good because it
forces the decision. If all variables have been accounted for, and you're still unsure, why not just flip a coin? It's no less arbitrary than anything else one might do.