The voice of the mind is not the truth
As soon as we wake up in the morning the voice of the mind starts commenting and interpreting every situation that arises. Listening to that voice is not a conscious choice, but a habitual reflex that starts the moment we open our eyes.
We know that the mind is filled with information from outside that we have internalised. These messages don't describe who we are, they depict what others have projected onto us. For as long as there is no other information available to us, we accept these projections as true descriptions of who we are.
Once we have the good fortune of learning about the existence of the Self, we become aware that the mind's vision is limited and bound by duality. It is always telling us what we are not. The mind says: believe in me, I am real - when in fact it is a mere shadow of our True Nature, the unchanging Self.
The Knowledge of the Self is unfolded in Meditation when we experience it directly. This experience becomes the guidepost or reference point we can remember during the day, moment to moment.