Sen Ts’an

Sen-Ts’an was an eighth-century Chinese Zen master who wrote:

   The Perfect Way is only difficult for those who pick and choose;

   Do not like, do not dislike; all will then be clear.

   Make a hairbreadth difference,

   and Heaven and Earth are set apart;

   If you want the truth to stand clear before you,

   never be for or against.

   The struggle between “for” and “against” is the mind’s worst disease.

Who was Sen Ts’an?

Sen Ts’an is an older spelling of Sengcan (Seng-ts’an, Japanese Sōsan), honoured as the Third Patriarch of Chan (Zen) Buddhism in China. Tradition says he received the teaching from the Second Patriarch, Huike, and died around 606 CE, which places him in the late sixth century rather than the eighth. The poem above is from the Xinxin Ming, usually translated “Verses on the Faith-Mind” or “Inscription on Trusting the Mind”. Modern scholars doubt Sengcan actually wrote it; it may come from a later Chan author in the Tang dynasty. Either way, it has been one of the best-loved texts of Zen for over a thousand years.

The plain idea

The poem’s claim is radical and simple: suffering comes from the mind dividing the world into opposites and then clinging to one side. Like and dislike, good and bad, mine and yours, success and failure. The Perfect Way (the Tao, or reality as it is) is not difficult in itself; it only becomes difficult when we pick and choose. Drop the preferences and things “will then be clear”.

This is not a recommendation to stop caring or to become a doormat. It is an observation about attention. The moment you insist that the world must be one way and not another, you stop seeing what is in front of you, and you start fighting it.

Why it matters

It is a concise statement of a theme that runs through Chan and Zen, Taoism and Indian non-dualism (see Advaita): reality is not split the way our concepts split it.
It anticipates insights from modern psychology. Acceptance-based therapies (such as Acceptance and Commitment Therapy) and mindfulness programmes train people to notice thoughts and preferences without automatically obeying them, and there is reasonable evidence that this reduces anxiety and rumination.
It challenges a habit the West prizes: always having an opinion. “The struggle between for and against is the mind’s worst disease” is an uncomfortable line in an age of permanent online argument.

An everyday analogy: the traffic jam

You are stuck in traffic. The traffic is just traffic: cars, time, a road. Then the mind adds “this shouldn’t be happening”, “I’m going to be late”, “that idiot cut in”. Now there are two problems: the traffic and your war with it. The poem is pointing at the second one. You still might take a different route tomorrow, but right now the extra suffering is optional.

A worked example: reading one line closely

“Make a hairbreadth difference, and Heaven and Earth are set apart.”

The literal claim: a tiny distinction in the mind opens a vast gap.
What the “hairbreadth” is: the first flicker of preference, I like this, I don’t like that.
Why it becomes vast: each preference breeds others. I like praise, so I fear criticism; I fear criticism, so I hide mistakes; I hide mistakes, so I can’t learn. One small split, a whole life arranged around it.
The practice it implies: notice the flicker early, before it hardens into a position. Zen meditation is largely training in exactly this noticing.

Where the poem goes next

The lines quoted at the top are only the opening. The Xinxin Ming runs to 146 short lines, and it keeps returning to the same move from different angles. It warns against chasing emptiness just as much as chasing things, since “emptiness” can become one more opinion to cling to. It says that trying to stop activity in order to be still only produces more activity. And it ends with the line many translators render as “words! the Way is beyond language”, a reminder that even this explanation is a finger pointing at the moon, not the moon. That self-undercutting ending is very Zen: the poem refuses to become one more thing to be for.

Common misconceptions

“Never be for or against” means having no ethics. Chan teachers kept strict monastic precepts. The point is not to stop acting well but to stop being driven by attachment and aversion.
“It’s anti-thinking.” It is against clinging to thoughts, not against using them.
“It’s a mystical riddle.” It reads more like practical advice than a puzzle. Try it on any small irritation today.

How it connects

Advaita: Indian non-dual philosophy, a close cousin.
Dao De Jing: the Taoist roots of Chan.
Meditation and Spiritual for practice.
Philosophy for the wider map.

The truth revealed: the Way was never hard. We made it hard by insisting it go our way.