What is Buddhism? The Buddha's teaching, explained

Buddhism is the religion and way of life founded on the teaching of Siddhartha Gautama, the Buddha, "the awakened one", who lived in northern India about 2,400 to 2,500 years ago. It teaches that life is marked by dissatisfaction, that the cause is craving, and that a path of ethics, meditation and wisdom can end it in a state called nirvana. In 2020 there were about 324 million Buddhists.

In short

• The Buddha's core teaching is the Four Noble Truths: there is suffering, it has a cause, it can end, and the Eightfold Path is the way.
• Buddhism has no creator God at its center; it teaches karma, rebirth and the release from rebirth, nirvana.
• Its three great traditions, Theravada, Mahayana and Vajrayana, share that core but differ in texts, ideals and practice.

Who was the Buddha?

Siddhartha Gautama was born into a ruling family of the Shakya people at Lumbini, in today's Nepal near the Indian border. His dates are uncertain. Tradition long placed him at about 563 to 483 BCE, but many scholars now think he died around 405 BCE (Stanford Encyclopedia of Philosophy). Tradition holds that he lived to about 80.

It helps to separate what is broadly accepted from what is tradition. Historians accept that he was a real teacher who left home to live as a wandering ascetic, taught for decades in the Ganges valley, gathered an order of monks and, later, nuns, and died at Kushinagar. The traditional story adds much more: a prince raised in luxury who, at 29, saw an old man, a sick man, a corpse and a holy man, left his palace, tried and abandoned extreme fasting, and attained awakening while meditating under a tree at Bodh Gaya. He gave his first teaching in a deer park at Sarnath, near Varanasi. The story carries the teaching, a "middle way" between indulgence and self-denial, even where its details cannot be checked. His teachings were passed down orally for centuries and first written down, in the Pali language, in Sri Lanka in the 1st century BCE.

What are the Four Noble Truths?

The Four Noble Truths are the Buddha's diagnosis of the human condition, set out like a doctor's: the illness, its cause, the cure and the treatment (BBC Religions).

1. Dukkha. Life is marked by suffering. The Pali word is broader than pain: it covers the frustration and unease of a world in which nothing lasts.
2. The cause. Dukkha arises from craving, tanha, literally "thirst": wanting pleasant things to stay, unpleasant things to go, and the self to be secure.
3. The end. Craving can be ended, and with it dukkha. That end is nirvana, "blowing out", as a flame goes out when its fuel is gone.
4. The path. The way to it is the Noble Eightfold Path.

Take an everyday case. A person buys the phone they have wanted for months. The pleasure is real, and it fades within weeks; then the screen cracks and they are upset, and soon they want the next model. The Buddhist analysis is not that the phone is bad. It is that the unease comes from holding on to something that, like everything, changes, and that seeing this clearly loosens the grip. The same analysis is applied, much more seriously, to illness, ageing, loss and death.

Behind the truths lie three marks of existence: everything conditioned is impermanent (anicca), unsatisfactory (dukkha) and without a fixed self (anatta). The last is the most distinctive. Buddhism teaches that there is no permanent soul behind a person, only a changing stream of body, feelings, perceptions, mental formations and consciousness. Karma, intentional action, shapes that stream, and it continues from life to life in rebirth until nirvana ends the cycle.

What is the Eightfold Path?

The Eightfold Path is the practical side of the teaching, and its eight parts are traditionally grouped in three.

Group	Parts of the path	In practice
Wisdom	Right view, right intention	Understanding the Four Noble Truths; intending kindness rather than harm
Ethical conduct	Right speech, right action, right livelihood	No lying or harsh speech; no killing, stealing or sexual misconduct; work that harms no one
Meditation	Right effort, right mindfulness, right concentration	Training attention and calming the mind

"Right" here translates a word meaning complete or fitting, not "correct according to a rule". The parts are practiced together, not one after another. For lay Buddhists, ethics usually takes the form of five precepts: to refrain from killing, stealing, sexual misconduct, false speech and intoxicants. Monks and nuns keep many more rules. Much Buddhist practice is also devotional: bowing to images of the Buddha, making offerings at temples and stupas, chanting, and giving food to monks.

What are the main traditions of Buddhism?

As Buddhism spread across Asia over two millennia, it formed three great traditions, and many schools within them.

	Theravada	Mahayana	Vajrayana
Name means	"Teaching of the elders"	"Great vehicle"	"Diamond vehicle"
Where practiced	Sri Lanka, Myanmar, Thailand, Cambodia, Laos	China, Japan, Korea, Vietnam, Taiwan	Tibet, Bhutan, Mongolia, parts of Nepal and Russia
Main texts	The Pali Canon	Mahayana sutras, such as the Lotus Sutra and the Heart Sutra, alongside earlier texts	Mahayana texts plus tantras
Ideal	The arhat, who attains nirvana through their own practice	The bodhisattva, who seeks awakening to free all beings	The bodhisattva, reached faster through ritual and the guidance of a teacher, a lama
Known for	Monastic life; insight meditation	Many schools, including Zen and Pure Land	Visualization, mantras, mandalas; the Dalai Lama

Vajrayana is often counted as part of Mahayana, which is why some sources speak of two traditions, not three. The differences are real, but every tradition keeps the Four Noble Truths, karma, rebirth and the goal of release.

How many Buddhists are there?

Pew Research Center estimated 324 million Buddhists in 2020, 4.1% of the world's population. They were the only major group that shrank between 2010 and 2020, by about 19 million, partly because they are concentrated in countries such as China and Japan, whose share of the world's population is falling, and partly because more people left Buddhism than joined it (Pew Research Center, 2025). Counting is hard: in China and Japan many people take part in Buddhist rites without calling themselves Buddhists.

Buddhism also left India. It grew out of the same world of ideas as Hinduism, sharing karma, rebirth and the goal of liberation, but rejected the authority of the Vedas and the caste system. It flourished there for over 1,500 years and then largely disappeared from the country of its birth by the 13th century, surviving in the countries it had reached.

Is Buddhism a religion or a philosophy?

Both descriptions are defended, and the answer depends on what a definition of religion demands.

Still argued

Those who call Buddhism a philosophy point out that it has no creator God, asks followers to test the teaching in experience rather than take it on faith, and has a long tradition of logic and argument, which is why the Stanford Encyclopedia of Philosophy treats the Buddha as a philosopher. Those who call it a religion point to what most Buddhists in Asia actually do: worship at temples, pray to buddhas and bodhisattvas, honor relics, keep monastic orders, and believe in rebirth, heavens and hells. Many scholars answer that the question itself comes from a Western split between religion and philosophy that Buddhist traditions never made.

In the West, Buddhism is often met as mindfulness or meditation for stress, but that is a small, modern slice of it. The tradition's goal is not a calmer week but the end of craving and rebirth. Readers who know Stoicism will notice an overlap, since both trace distress to the mind's own judgments and attachments, and both ask what makes a life go well. The answers differ: the Stoics place the good in virtue in this life, while Buddhism seeks release from the cycle of lives.

Check yourself

• Without looking back, state the Four Noble Truths as a doctor's diagnosis: illness, cause, cure, treatment.
• What does "no self" mean in Buddhism, and how can rebirth work without a soul?
• What separates the ideal of the arhat from that of the bodhisattva?

Sources

• The Buddha — Stanford Encyclopedia of Philosophy, Mark Siderits, 2023
• The Four Noble Truths — BBC Religions, 2009
• Theravada Buddhism — BBC Religions, 2002
• How the Global Religious Landscape Changed From 2010 to 2020 — Pew Research Center, 2025
• Buddhism — World History Encyclopedia, Joshua J. Mark