For Schopenhauer, Will had ontological primacy over the intellect; in other words, desire is understood to be prior to thought. Schopenhauer felt this was similar to notions of purushartha or goals of life in Vedanta Hinduism.

In Schopenhauer's philosophy, denial of the will is attained by either:
— personal experience of an extremely great suffering that leads to loss of the will to live;
— knowledge of the essential nature of life in the world through observation of the suffering of other people.

However, Buddhist nirvana is not equivalent to the condition that Schopenhauer described as denial of the will. Nirvana is not the extinguishing of the person as some Western scholars have thought, but only the «extinguishing» (the literal meaning of nirvana) of the flames of greed, hatred, and delusion that assail a person's character.

//an extract from Wiki article