Henry Ford said "If you think you can, you are right. If you think you can't you are right too."
Napoleon Hill said "What the mind can conceive and believe, you can achieve."
I say, you will see it when you believe it, not the other way around. If you believe life is good, you will see evidence of this fact. If you believe life is a dog eat dog world, well you sill see evidence of this too.
Your beliefs are formed at a very early age. They get downloaded into your subconscious mind from the people who influenced you and the things you saw and heard. The thoughts you think that are true in your mind, are what you believe to be true in your reality. Your beliefs are a bundle of thoughts that you have been thinking for a long time. They can change.
The Law of Attraction tells you that what you think is what you attract. The creation of your reality is shaped by the thoughts you think and waves of energy they carry. For instance, if you believe negative things will happen in your life, most likely, you will attract unpleasant experiences. Your thoughts are like electricity you send out into the field of possibilities and your feelings are the magnetic draw that gets returned or attracted back to you. You are actually and electromagnetic broadcasting energy source.
Then when those unpleasant experiences happen, you sit and wonder why does this always happen to me? How many times have you said that to yourself during the course of your day or in the midnight hour. Well first of all, you must become conscious of the dialog you are having with yourself. If you say to yourself why is this always happening to me? Right there it will always happen because you believe that it always will. Believability is what leads to your actions and circumstance of your life.
Your beliefs come from how you were raised by your parents or how you were influenced growing up as a kid. The information you became fed with is how you were programmed to think. It was either positive beliefs or negative beliefs, or both perhaps. Regardless of the fact, you want to create new beliefs which transmute the negative beliefs and have more of a positive belief system.
Negatives are good when you deal with them immediately, You become aware of the thoughts that you are thinking and your feelings. You can then change them. You then change your energy field. You cannot let the negative thoughts hang out for too long. That's when the wrong deposits are made into your subconscious mind. You must replace the negative thought with a positive so you reduce the risks of developing negative emotions. Your beliefs manifest your reality through your thoughts and emotions. You maintain your positive belief system by doing positive things on a daily basis. New beliefs will form which will lead to a happy and productive life.