"Trika" means "threefold". One interpretation states that Non-dual Shaivism of Kashmir is known as Trika or Threefold System because it analyzes the nature of Śiva, Śakti and Nara. Śiva is God, and Śakti is God's I-consciousness. Nara is man (the human being). Trika teaches that Śiva, Śakti and Nara are not different from one another. In short, Man and God are one and the same. In fact, just the Supreme Self, known as Śiva in this philosophical system, is the Self of the entire universe. There is no difference between Śiva (God) and Śakti (God's I-consciousness). God is and knows He is. There is no difference at all. On the other hand, Śiva is a name for the static aspect of God, while Śakti is a name for the dynamic aspect of God. Thus, Śiva-Śakti is Freedom Itself. Consequently, the human being is inherently free too.
However, the human being experiences bondage because of "mala" (limiting condition). Nevertheless, this "mala" is not something outside of the human being himself. God becomes "man" (so to speak) through "mala" (impurity, limiting condition). In other words, mala arises from God.
Śiva or God is not inactive. He has Śakti or I-consciousness. In short, He has Will, which gives rise to Knowledge and Activity. When a human being realizes his inherent unity with Śiva and Śakti, "mala" (limiting condition) ceases to exist completely. This realization puts an end to the whole "apparent" bondage.
Since a human being is essentially God, he manifests the entire universe around him. Even though Non-dualism between God and the human being is predominant in this philosophical system, all other dualistic viewpoints are explained and included too.
The universe is the playful unfoldment of God's power. Therefore, the universe is born right now from Joy. Unhappiness is experienced by a human being when he becomes oblivious of his spiritual nature. When he remembers his spiritual nature and realizes his unity with God, unhappiness is turned into happiness. Therefore, mala or impurity is nothing but ignorance of one's essential nature.
Trika also teaches that the human mind is Śakti Herself having undergone a process of successive contractions. Therefore, the mind experiences complete happiness only when it merges in God. God is not a void at all but rather a Self full of I-consciousness.
The human being must understand that his own mind is the Divine Mind having undergone a process of succesive contractions. Consequently, understanding of one's mind is encouraged, not simply the control of it. To control the mind, as it were, one must first understand it.