Acharya Prashant explains that peace is not a state of mind that can be achieved, lost, or experienced. He clarifies that common notions of peace as a temporary state of stillness or emptiness are incorrect because anything that comes and goes cannot be true peace. Peace is not a color or a specific condition of the mind like jealousy or joy; rather, it is the very foundation and center of our existence. He emphasizes that peace is eternal and constant, and the belief that it has been lost is a misconception often fueled by those who wish to sell methods or books to 'find' it.