What are the three Dharma seals?

The three Dharma seals of Buddha's teaching are impermanence, nonself and nirvana. Impermanence is not merely a philosophy, but must be practiced and nourished in daily life. Impermanence and nonself are the same, impermanence related to time and nonself to space. Impermanence itself does not cause suffering, but the desire that it not be so does. Practicing impermanence helps us cherish what is around and inside us. Impermanence makes transformation possible; if we live mindfully we appreciate fully every moment, knowing everything is impermanent, touching the "foundation of reality." Being and nonbeing are only notions. Hanh says nothing is ever lost or gained.