The quintessence of Gandhian thought, or the most essential aspect, is Satyagraha. Satyagraha is a nonviolent resistance or civil disobedience approach that Gandhi promoted during India`s struggle for independence. It involves actively resisting injustice and oppression through peaceful means, such as protests, boycotts, and strikes.

Metaphysics, which refers to the branch of philosophy that deals with the nature of reality or existence, is not the quintessence of Gandhian thought. While Gandhi did have a deep spiritual and philosophical inclination, metaphysics does not capture the essence of his teachings.

Spiritualism is closely aligned with Gandhi`s beliefs, as he emphasized the importance of moral and ethical values, truthfulness, and spirituality in one`s personal and political life. However, it is not the quintessence of his thought.

Moksha, a concept in Hindu philosophy, refers to liberation from the cycle of birth and death through spiritual enlightenment. While it may have influenced Gandhi`s thinking, it is not the central focus of his ideology.

In summary, Satyagraha best represents the core principle of Gandhi`s philosophy, emphasizing nonviolent resistance as a means to achieve social and political justice.