Whatever can be described cannot be your self, and what you are cannot be described. You can only know your self by being yourself without any attempt at self-definition and self-description. Once you have understood that you are nothing perceivable or conceivable, that whatever appears in the field of consciousness cannot be your self, you will apply yourself to the eradication of all self-identification, as the only way that can take you to a deeper realisation of your self. You literally progress by rejection -- a veritable rocket. To know that you are neither in the body nor in the mind, though aware of both, is already self-knowledge.