Understanding how your brain works will help you make better decisions, be more motivated, achieve the things you want, and be happier.
Your brain is divided into two parts; the intuitive (automatic) system and the cognitive part. You are only aware of your cognitive part of your brain, but most decisions are made by your intuitive part of the brain.
The intuitive part controls the way you walk, breathe, eat, but it also makes decisions regarding problems you have already solved in other situations like adding 1 to 1 and it also sends impulses to your conscious part when making decisions. Being an automatic system, it does not require a lot of effort to work, you never even realize it’s working.
The cognitive part is in charge of solving problems, making decisions for the first time, feelings and consciousness. It’s your cognitive part which involves awareness and the self consciousness. This is your voluntary system, the one that you control, but since it requires your control and attention to run, it also uses a lot of energy.
In this hierarchy, the cognitive system is the one in charge, the one capable to over-ride your automatic system and able to make decisions. The problem is that doing so requires a lot of energy and most of times your brain will rather save that energy and just go with the impulses received from your automatic system.
Living your life by instinct might sound like a good idea, but your automatic system is prone to make certain mistakes, to answer a question it has no answer for with the answer from another similar question, and to make false connections.
Without thinking really hard, give the first answer that comes into mind to the following problem: “A ball and a bat cost 1.10$. How much does the ball cost if you know the bat is 1$ more expensive?”. More than half of people will respond 0.10$. This is a classic case of mistakes your brain will do while working only in automatic mode.
Your automatic system, even if efficient in many cases, has its limitations. A constant moderate control from your conscious system can prevent some unwanted mistakes.