The First Noble Truth: The Existence of Duhkha. All phenomena are inadequate and unsatisfactory, and its nature is suffering from impermanence. If the nature of changing is not understood, it will be the cause of pain, sorrow, and unhappiness, such as the basic situations in everyone’s life: birth, aging, sickness, and death. In addition, to be with the unwanted, to be detached from loved ones, and to be not fulfilled from desires are also painful.