All dharmas are originally nonexistent. To think that they exist causes attachment. If they do not exist, to say perversely that they do is also attachment. One neither thinks of these two, nor does one incline to what is between them. It is for this reason alone that they are not on either side, nor in the middle, they neither exist, nor do they not exist. Why? All dharmas are empty; they are like nirvāṇa; they are indestructible, imperishable, and unsteady; they are neither here nor there, they are markless, they are unwavering.

— The Pratyutpanna Samādhi Sūtra

This passage deploys one of Indian philosophy's most sophisticated logical tools: the catuṣkoṭi, or "four corners." Western logic typically offers two options—something either is or is not. The tetralemma adds two more: both is and is not, and neither is nor is not. Then, remarkably, this sutra rejects all four. The mind accustomed to binary thinking finds itself without a place to land.

But first we need to understand what's being negated. The word dharmas here doesn't mean the Buddha's teachings. It refers to phenomena—the basic constituents of experience that Abhidharma scholars catalogued in elaborate lists. Think of them as the building blocks of reality: physical forms, sensations, perceptions, mental formations, moments of consciousness. Everything we can possibly experience breaks down into dharmas. The sutra is making a claim about the fundamental nature of all that exists.

"All dharmas are originally nonexistent." Already we're in difficult territory. The sutra doesn't say they don't exist—it says they are originally nonexistent. They lack inherent, independent being. They arise through causes and conditions, dependent on everything else, possessing no fixed essence of their own. But then the trap: "To think that they exist causes attachment." We grasp at phenomena as though they were solid, permanent, truly there in the way they appear to be. This grasping is the root of suffering.

The opposite error is equally dangerous. "If they do not exist, to say perversely that they do is also attachment." Nihilism—denying that anything exists at all—is just another position the mind clings to. The negation becomes its own object of grasping. We've traded one attachment for another.

Now comes the catuṣkoṭi's full force: "One neither thinks of these two, nor does one incline to what is between them." Not existence, not nonexistence, not some middle ground between them, and—implicitly—not the rejection of all three either. Every position the conceptual mind might take has been foreclosed. "They are not on either side, nor in the middle, they neither exist, nor do they not exist."

What's left when every position has been abandoned? The sutra answers: emptiness. But emptiness isn't a fifth position to cling to. It's what remains when clinging stops. "All dharmas are empty; they are like nirvāṇa." Notice the comparison—phenomena share the character of liberation itself. Not because they're holy or special, but because their nature, when seen clearly, offers no foothold for attachment. "Indestructible, imperishable, and unsteady"—these apparent contradictions point beyond conceptual thought. "Neither here nor there, markless, unwavering."

The catuṣkoṭi isn't meant to produce a headache, though it often does. It's a therapeutic tool. The mind that grasps at positions—this is how things are—creates its own prison. Each view becomes a wall. The tetralemma systematically removes the walls until the mind, unable to find anywhere to perch, simply opens. This opening isn't an intellectual achievement. It's what happens when conceptual elaboration exhausts itself. We don't arrive at emptiness through reasoning; reasoning clears the space for emptiness to reveal itself.

In meditation, this becomes practical rather than abstract. Thoughts arise—we notice ourselves taking positions, forming views, constructing a world of things that exist or don't exist, that we want or reject. The practice isn't to adopt better positions but to recognize the positioning itself as the problem. When that recognition deepens, something shifts. The dharmas don't disappear—the world remains vivid, immediate, fully present. But the grasping that made it feel solid and separate relaxes. What's left isn't nothing. It's everything, no longer divided against itself.