Prajna is Sanskrit for "wisdom." Panna is the Pali equivalent, more often used in Theravada Buddhism. But what is "wisdom" in Buddhism?

The English word wisdom is linked to knowledge. If you look the word up in dictionaries, you find definitions such as "knowledge gained through experience"; "using good judgment"; "knowing what is proper or reasonable." But this is not exactly "wisdom" in the Buddhist sense.

This is not to say that knowledge isn't important, also. The most common word for knowledge in Sanskrit is jnana. Jnana is practical knowledge of how the world works; medical science or engineering would be examples of jnana.

However, "wisdom" is something else. In Buddhism, "wisdom" is realizing or perceiving the true nature of reality; seeing things as they are, not as they appear. This wisdom is not bound by conceptual knowledge. It must be intimately experienced to be understood.

Prajna also is sometimes translated as "consciousness," "insight" or "discernment."

Wisdom in Theravada Buddhism

Theravada stresses purifying the mind from defilements (kilesas, in Pali) and cultivating the mind through meditation (bhavana) In order to develop discerning or penetrating insight into the Three Marks of Existence and the Four Noble Truths. This is the path to wisdom.

To realize the complete meaning of the Three Marks and Four Noble Truths is perceiving the true nature of all phenomena. The 5th-century scholar Buddhaghosa wrote (Visuddhimagga XIV, 7), "Wisdom penetrates into dharmas as they are in themselves. It disperses the darkness of delusion, which covers up the own-being of dharmas." (Dharma in this context means "manifestation of reality.")

Wisdom in Mahayana Buddhism

Wisdom in Mahayana is linked to the doctrine of sunyata, "emptiness." The Perfection of Wisdom (prajnaparamita) is the personal, intimate, intuitive realization of the emptiness of phenomena.

Emptiness is a difficult doctrine often mistaken for nihilism. This teaching does not say that nothing exists; it says that nothing has independent or self-existence. We perceive the world as a collection of fixed, separate things, but this is an illusion.

What we see as distinctive things are temporary compounds or assemblies of conditions that we identify from their relationship to other temporary assemblies of conditions. However, looking deeper, you see that all of these assemblies are interconnected to all other assemblies.

My favorite description of emptiness is by Zen teacher Norman Fischer. He said that emptiness refers to deconstructed reality. "In the end, everything is just a designation," he said. "Things have a kind of reality in their being named and conceptualized, but otherwise they actually aren’t present." 

Yet there is a connection: "In fact, connection is all you find, with no things that are connected. It’s the very thoroughness of the connection -- no gaps or lumps in it -- only the constant nexus -- that renders everything void. So everything is empty and connected, or empty because connected.  Emptiness is connection." 

As in Theravada Buddhism, in Mahayana "wisdom" is realized through the intimate, experienced discernment of reality. To have a conceptual understanding of emptiness is not the same thing, and merely believing in a doctrine of emptiness isn't even close. When emptiness is personally realized, it changes the way we understand and experience everything -- that is wisdom.