In the Buddhist tradition, Mettā is a Pali word often translated as "loving-kindness," "goodwill," or "universal friendliness." It is derived from the word mitta, which literally means "friend."
Unlike romantic love (pema) or attachment, Mettā is an active, non-possessive wish for the well-being and happiness of all living beings, without exception. To explain this, we look primarily to the Karaniya Metta Sutta (The Discourse on Loving-Kindness), which is the most definitive text on the subject.
According to traditional commentaries, the Buddha taught this sutta to a group of monks who were trying to meditate in a forest but were being frightened by local tree-spirits. Rather than telling the monks to leave or fight back, the Buddha gave them the Metta Sutta as both a protection and a meditation. He taught them that by radiating goodwill, they would transform the hostility of their environment into peace.
The Karaniya Metta Sutta (Sn 1.8) begins by describing the character one must develop to truly practice Mettā. It isn't just a "feeling" you conjure up; it is a way of being. The sutta says a practitioner should be:
Upright and honest (not deceptive).
Gentle and humble (not arrogant).
Easily satisfied (frugal and content).
Calm and wise (not demanding).
"Let them not do the slightest thing that the wise would later reprove." — Karaniya Metta Sutta
The heart of the sutta describes how to expand your heart. It asks you to include every possible category of being in your wish for happiness:
The Physical: Weak or strong, tall or short, large or small.
The Spatial: Seen or unseen, living near or far away.
The Temporal: Those already born and those yet to be born.
The most famous instruction in the sutta uses the metaphor of a mother’s love:
"Even as a mother protects with her life her child, her only child, so with a boundless heart should one cherish all living beings." — Karaniya Metta Sutta
In another discourse, the Metta Anisansa Sutta (AN 11.16), the Buddha lists eleven specific benefits for those who practice loving-kindness consistently. If you cultivate Mettā, the sutta promises that:
You sleep easily.
You wake easily.
You have no bad dreams.
You are dear to human beings.
You are dear to non-human beings.
Devas (celestial beings) protect you.
Fire, poison, and weapons cannot harm you.
Your mind concentrates quickly.
Your facial expression is serene.
You die unconfused.
If you don't reach full enlightenment, you are reborn in the Brahma realms.
The suttas and their commentaries distinguish Mettā from two "enemies" that can sneak into the practice:
The Far Enemy (Hatred): This is obvious ill-will. Mettā is the direct antidote to anger.
The Near Enemy (Sentimental Attachment): This is more subtle. It feels like love, but it is "sticky" and selfish. True Me
Mettā does not exist in isolation; it is the first of the Four Divine Abodes (Brahmavihāras), which are considered the highest emotional states a person can cultivate. In the suttas, these are described as "boundless" or "immeasurable" because they are practiced without limit or partiality.
While Mettā is the foundation—the general wish for the well-being of others—it transforms into the other three states depending on the situation:
Karuṇā (Compassion): When Mettā encounters suffering, it becomes the desire to remove that suffering.
Muditā (Empathetic Joy): When Mettā encounters the success or happiness of others, it becomes a feeling of joy instead of envy.
Upekkhā (Equanimity): This is the "even-mindedness" that keeps Mettā stable, ensuring your kindness is not shaken by the behavior of others or the ups and downs of life.
Together, these four qualities create a balanced heart. Mettā provides the warmth, Karuṇā the action, Muditā the celebration, and Upekkhā the steady foundation that prevents you from becoming overwhelmed.