You do not, hun 😉
I am quite the smart person and I know for a fact that there are things about me that I do not know 🙂
The human mind is a horribly advance device. Do you know for example that the way you write by hand can be analyzed to describe your current state of mind? 😉
Your handwriting is effected by your subconcious and the subconcious is nothing you can effect 😄 Same goes with the voice, that too is adapted by your current state. Some claim to be able to speak emotionless but that is a lie 😉