What drives you to make the decisions that you make, believe the things your believe, and do the things you do? Are you following in someone else's footsteps, and that path defines your motives? Or, and this is slightly more interesting, are you following in the footsteps of your previous self, or your ideal self?
When you do the things you do, do you do them because you've rationalized that this is the right thing to do, or does the right thing come from your spine?
Sometimes you act on impulse, doing things as if from muscle memory even if you've never been in such a situation or never acted that way before. The reaction might be based on the survivalist animal instinct within you, especially if you have no time to think. When something is metaphorically pulling you from the waist in a certain direction, you don't stop to think. You go.
At the end, you'll need to be able to live with yourself. Supposedly.
What makes instinctual reactions complicated are their ability to cause you to do something you'll regret, something that'll make it hard for you to live with yourself. This isn't always the case, though. If your instinct calls you to defend a loved one, you don't stop to think the consequences. You go and defend your loved one.
Then there are situations in which your instinct speaks less loudly: those life-defining choices between what is right and what is easy, what is you and what is someone else, what gives meaning and what does not. There are a million little things trying to win you over to their side, screaming and shouting; yet the voice that speaks in a whisper or might even stay completely quiet, waiting for its turn to speak, is your instinct.
Whether listening to it and going with it allows you to live with yourself with more ease than the other option, depends on you.