There is no biological and scientific explanations to this ever present voice but you see, we all hear them. For some the voice is the all-commanding mentor. It is sad though that for some, this little voice has become their inner critic, or worse has for a long time muted. It is an innate murmuring voice that we hear. One, destroys a person's credibility and the other intensifies his personality. And obviously, you would not want the consequences of being too confident of yourself that the people no longer view you as effective, instead they see you as annoyance to their daily affairs. Self confidence comes from within. What matters more is that you have atleast removed yourself from the old ways that you have learned to embrace. The only place from which we may start is within ourselves. For long, we fed ourselves with impressions coming from the people we are interacting with. For long, we have practiced comparing what we can and what we cannot do with other people. The only certain way though to achieving this is from within. We have to create a self concept that is focused on our attributes and not on our lacks. On our achievements and not on our defeats. On our own fence and not on the fence of a neighbor or of someone greater than us. We also must inculcate in us values that are helpful in recreating our self image and self worth. We were all born entitled with achievements and successes. The Universe is too good for us that she took time to secure everything that we would need to soar. Don't waste this very opportunity by putting loads in your back so you would be delimited and thus, incapable of flying. Be like an eagle who has unearthed himself from the mud of being a chicken. You may start with talking to yourself using positive statements like "you are great" (for you truly are a great individual waiting for your talents to be tapped). Or "you are beautiful" (because believe in this or not each one of us were created beautifully to give glory to our Maker).