Heart or Brain..

Commonly we say dont have two minds when you are taking some important decisions in life. What are these two minds? I think this refers to the "Heart" and "Brain". What is the difference between them even though both are in the single body.

For Instance, when we are thinking about some decisions we need to take in life, we will be in huge struggle like what will happen later when i do like this. and why cant i do it in the other way? what makes us to think like this. Some they say for a particular situation do what heart says! and in the other do as Brain Says!. Heart always tell what you want in life . But Brain always tell what are the way to do it and what will happen if you do it. Brain analyzes both the positive and negative things about the particular situation. There is always a conflict between the two. Heart will say lets do it. But brain say dont do, if you do this the effect will be like this ( it will simulate the scenario in the mind). So usually it is very difficult for us to take a decision. For Example, When you want a particular girl in your life. Heart will say i like the girl lets try it and get it. But brain will put a hurdle saying some after effects you may face when u approach the girl. Finally we will be in the confusing state, by which one we have to take in to account and take action.. Heart or Brain??