The Parable of the Medicinal Herbs—One Rain, and Roots That Differ

7.5 The Parable of the Medicinal Herbs—One Rain, and Roots That Differ

The parable of the prodigal son in the previous chapter cured a certain misrecognition—the śrāvaka had read his own liberation as though it were the same as the Buddha's liberation. "My vehicle is no different from the Tathāgata's vehicle"—Vasubandhu called this the śrāvaka's upward flattening. The cure was to make him recognise that he was in truth a poor son who had spent twenty years hauling out the mire: the right of inheritance was still his, but the work was not yet done.

The parable of the medicinal herbs in this chapter cures the mirror-image opposite of that mistake—the Mahāyāna practitioner's downward erasure.

A student of the Mahāyāna who has just finished the previous chapters can easily come away with this impression: since ultimately there is only one buddha-vehicle, are not the distinctions between śrāvaka, pratyekabuddha, and bodhisattva simply something we no longer need to bother with? Since the three vehicles are an expedient, is it not the case that "everyone is really walking the same one road"? Since one was the elder's son all along, should not every distinction be abolished?

Vasubandhu's Lotus Treatise calls this line of thought "the Mahāyāna's fixed conceit of unidirectional certainty"—the belief that "there is no separate śrāvaka or pratyekabuddha vehicle." This too is a way of "treating three as one," but its direction is exactly the reverse of the śrāvaka's upward flattening. The śrāvaka goes upward—raising himself to the height of the Buddha. The Mahāyāna person goes downward—pressing flat all the distinctions below.

What the parable of the medicinal herbs sets out to do is cure this downward erasure.

The Cloud and Rain of the Great Trichiliocosm

The story begins with an exceedingly vast camera.

The opening of the "Medicinal Herbs" chapter pushes us all at once to a cosmic scale—not a great mansion, not a single household, but the whole great trichiliocosm. The sūtra writes:

Suppose, in this great trichiliocosm, on its mountains, valleys, plains, and lands, there grow herbs, trees, groves, and medicinal plants of many kinds, varied in name and appearance. A dense cloud spreads everywhere, covering the whole trichiliocosm; in a single moment its rain falls equally, and its moisture penetrates all.

Let this picture rest a moment.

The great trichiliocosm—this is the largest unit in Buddhist cosmology, embracing countless suns and moons, mountains and rivers, worlds. At this scale, the plants that grow from valley and plain, forest and grassland, desert and wetland, from every climatic zone, are "of many kinds, varied in name and appearance"—no two are alike. Great trees soar into the clouds, small grasses creep along the ground, mid-sized shrubs stand between the two. Medicinal herbs alone number in the thousands, each with its own shape, colour, use, and rhythm of growth.

Then a dense cloud spreads everywhere—a vast cloud covers the whole great trichiliocosm. And then "in a single moment its rain falls equally"—all the rain comes down at once. For all the plants at once. Not sorted by size, not by kind, not by location, not by high or low.

The mark of this rain is equality. But:

The herbs, trees, groves, and medicinal plants—those of small roots, small stems, small branches, small leaves; of medium roots, medium stems, medium branches, medium leaves; of large roots, large stems, large branches, large leaves; trees of every size—each receives according to its high, middle, or low nature. From the one cloud's rain, in accordance with the inherent nature of each kind, they grow, blossom, and bear fruit. Though grown from one earth and moistened by one rain, the various plants have their differences.

Though the rain is the same one rain and the earth the same one earth, the plants each have their differences—those of small root and small stem absorb to the measure of small root and small stem, those of medium root and medium stem absorb to the measure of medium root and medium stem, those of large root and large stem absorb to the measure of large root and large stem. In accordance with their inherent nature—each according to its own disposition—they grow, blossom, and bear fruit.

Then the sūtra renders a crucial verdict:

Though grown from one earth and moistened by one rain, the various plants have their differences.

This "though... yet..." structure carries the whole doctrine of the medicinal-herbs parable. One earth, one rain—sameness. Each has its differences—difference. Both are true at once. This sentence should be read slowly, because it is one of the most concentrated dialectical statements in the entire Lotus Sūtra: sameness does not cancel difference, and difference does not tear apart sameness.

Then, in the dharma-correlation passage, the Buddha says:

The Tathāgata's teaching is of one mark and one taste—namely, the mark of liberation, the mark of detachment, the mark of cessation—ultimately reaching omniscience.

One mark and one taste—this is the rain itself. Liberation, detachment, cessation, omniscience—this is the content of the rain.

But the Buddha immediately continues:

Only the Tathāgata knows the categorical mark and intrinsic nature of these beings: what they think on, what they ponder, what they cultivate... by what dharma they think, by what dharma they ponder, by what dharma they cultivate, by what dharma they attain what dharma. Beings dwell in many different soils, and only the Tathāgata sees them as they are, with clarity and without obstruction.

"Only the Tathāgata sees them as they are"—note this limit. The difference in capacity is not something anyone can judge from the outside; only the Buddha's omniscience can fully perceive each being's categorical mark and intrinsic nature, what it is now cultivating, what it can attain. This limit matters—it separates two questions: "capacity-difference is real" and "who is able to judge that difference." The difference is a real fact, but judging the difference is not our work.

In the verse section, the Buddha goes further, mapping the grades of plants explicitly onto the grades of capacity:

From the smallest small herb to the largest large tree, five grades. Each has its own place, and each is in the rain.

Then comes the last and heaviest line of the verses, and of the whole chapter:

All you śrāvakas—none of you have entered final extinction. What you practise is the bodhisattva path; gradually cultivating, all of you shall become buddhas.

Difference is preserved right to the end—the three grasses and two trees, five portions each distinct. But the promise threads through everything—all shall become buddhas. Difference is not cancelled, the promise is not withdrawn. This is the dialectical closure of the parable of the medicinal herbs.

The Āgamas' "One Taste," the Lotus's "Difference"

The central image of the medicinal-herbs parable—cloud and rain moistening all, the earth thoroughly soaked—has deep seeds in the Āgamas.

The most direct kindred is the famous "one taste of the great ocean." The Ekottarika-āgama has a passage in which the Buddha likens eight qualities of the great ocean to eight qualities of the true Dharma and discipline. The fourth runs:

In my Dharma, all is of one taste, namely the taste of the eightfold noble path... just as the great ocean is wholly of one taste.

The parallel version in the Madhyama-āgama uses another comparison: "Just as the water of the great ocean is salt, all of one taste—Bālaka!—so too is my Dharma and discipline: its taste is desirelessness, the taste of awakening, the taste of stillness, the taste of the path."

What does "one taste" mean? It is a structure like this: no matter which river you enter the great ocean by—the Ganges, the Indus, the Vakṣu, the Sītā—once you have entered the ocean, your water merges with the ocean's water and no trace of its origin remains. In the same way, the four castes—Brahmin, Kṣatriya, Vaiśya, Śūdra—the most deeply rooted class-distinctions in Indian society—once they go forth, no longer call themselves by their original caste, but are all called śramaṇa.

This structure has other versions in the rhetoric of the Āgamas. In the Saṃyukta-āgama, the dialogue between Mahākātyāyana and King Madhura gives five tiers of argument proving that the four castes are completely equal in the Dharma—equal in karmic retribution, equal in legal standing, equal in the fruits of practice, equal in postmortem destination. The conclusion is: "It is only worldly speech that makes them differ; in truth, at the level of karma, there is no difference." Difference is only worldly speech; at the real level of karmic retribution there is no difference.

The Bieyi Saṃyukta-āgama even has a verse whose imagery is already very close to the Lotus:

It is as when a dense cloud blankets the world, with brilliant lightning and far-rolling thunder; it pours down great rain, and the earth is universally moistened; the herbs, trees, and groves are all without exception nourished.

"Dense cloud," "great rain," "earth universally moistened," "herbs, trees, and groves all without exception nourished"—almost exactly the opening of the "Medicinal Herbs" chapter.

But notice the last words of this verse—"all without exception nourished." Every plant is moistened, with no distinction at all. Nothing here is said about the three grasses and two trees receiving differently because of their own size.

This is the key difference between the Āgamas' "one taste" and the Lotus's "difference."

The Āgamas' one taste, rain of Dharma, equality of the four castes—the logic they all operate on is equality = elimination of difference. The four castes, once they go forth, have no more caste; the many streams, once they enter the ocean, become one taste; the thunder-rain, once it moistens all, leaves nothing unnourished. Every difference that enters this field is dissolved, erased, unified into the same single taste.

The logic of the Lotus's parable of the medicinal herbs is exactly the reverse—equality = inclusion of difference. The one cloud is still one cloud, the one rain still one rain, but the three grasses and two trees "each have their differences," "each receive according to their high, middle, or low nature," "in accordance with their inherent nature each grow, blossom, and bear fruit." Difference is not eliminated; on the contrary it is preserved, and is then declared, on a higher level, to be the very content of the equality that "all shall become buddhas."

This shift—from "equality through the elimination of difference" to "equality through the inclusion of difference"—is the Mahāyāna's dialectical innovation upon the Āgamic tradition. It is not a departure from the Āgamas' "one taste," but an expansion of the doctrinal room of "one taste" until it can hold difference at the same time. The Āgamas give the sameness in which the four castes, once they enter the saṅgha, become śramaṇa; the Lotus acknowledges that within "śramaṇa" there are the differing capacities of śrāvaka, pratyekabuddha, and bodhisattva, and builds upon that difference a larger sameness—all shall become buddhas. The former is a first-level sameness; the latter is a second-level sameness that holds the first level within it.

The Āgamas' equality is "no matter who you are, once you come in you are the same as everyone else." The Lotus's equality is "once you come in you are still yourself, and this 'still yourself' is exactly the starting point of the road you are to walk."

The Mirror of the Prodigal Son

Place the parable of the medicinal herbs back into the seven-parable system of Vasubandhu's Lotus Treatise, and it forms an exceedingly clear pairing with the parable of the prodigal son in the previous chapter.

Vasubandhu states it this way. He lists, one by one, the conceited minds of seven kinds of beings, each met by one parable as its antidote. The second parable (prodigal son) counters "the śrāvaka's fixed conceit of unidirectional certainty—who says of himself, my vehicle is no different from the Tathāgata's vehicle." The third parable (medicinal herbs) counters "the Mahāyāna's fixed conceit of unidirectional certainty—who thinks: there is no separate śrāvaka or pratyekabuddha vehicle." This too is "treating three as one," but in the opposite direction.

Two inversions, opposite in direction:

The śrāvaka goes upward—mistaking his own attainment for the buddha-state. The cure is the unifying movement of "treating three as one": you have not yet reached home, come gradually. The Mahāyāna person goes downward—pressing flat all the differences below. The cure is not the reverse "treating one as three," but letting you see that sameness and difference can both be true at once.

This asymmetry matters. Why is it not the reverse "treating one as three"? Because the Mahāyāna person's mistake is not a misjudgement of station but a misjudgement of logic—he infers "no difference" from "common source." Common source does not necessarily yield no difference, because equality can include difference. So the cure is not a reverse merging but a logical correction: you can hold both "the one vehicle" and "the three vehicles" at once, without cancelling either for the sake of the other.

Jizang's Fahua yishu extends this two-way cure into a triple structure—the burning house breaks the disease of ordinary beings, the prodigal son breaks the disease of the two vehicles, the medicinal herbs break the disease of bodhisattvas:

Three diseases each met by its cure, three cures each with its method. Ordinary beings do not know there is a way out, the two vehicles think they have already reached the top, the bodhisattva thinks the three vehicles are simply no different at all—the correction of these three errors constitutes the complete project of "position correction." By the time you read this far, the inner architecture of the Lotus's seven parables begins to show itself—it is not a scattered heap of parables but a carefully designed system of antidotes.

A Deep Divergence—Two Readings

The deepest interpretive divergence over the parable of the medicinal herbs falls on the question of where the difference in "each receives its portion of the moisture" comes from.

What is the difference among the three grasses and two trees? Is it a difference among the kinds of plant themselves—that is, a difference in the substance and category of the seeds? Or is it the difference of plants of the same kind at different stages of maturity, in different soil conditions—that is, a functional difference?

The Lotus text itself gives no direct answer to this. The sūtra says only "in accordance with their inherent nature each grow" and "only the Tathāgata sees them as they are." So the treatise systems each gave their own answer—and these answers form one of the deepest sets of divergences in the history of Lotus interpretation.

The functional reading: the Awakening of Faith and the Mahāyānasaṃgraha

The Awakening of Mahāyāna Faith, in the context of "the perfuming of suchness," raises the structural problem of the medicinal-herbs parable directly:

If this is the meaning, then since all beings possess suchness and are equally perfumed by it, why are there those of faith and those without, with measureless prior-and-later differences?

The structure of this question is exactly the same as the medicinal-herbs parable's—from the one cloud's rain, why do the plants each have differences? The Awakening of Faith answers:

Suchness is fundamentally one, but there is measureless and limitless nescience, which from the beginningless past has been substantially differing in thickness... So too with beings: although they have the perfuming-power of the right cause, if they do not encounter the buddhas, bodhisattvas, and good spiritual friends as conditions, they cannot of themselves cut off afflictions and enter nirvāṇa.

Where does the difference come from? Not from the presence or absence of seeds but from the thickness of nescience. The right cause that beings inherently possess (buddha-nature, suchness) is equal, but the thickness of the nescience covering that right cause differs. The thick is hard to penetrate, the thin easy to penetrate—the difference is a difference in the thickness of the obstruction, not a difference in the category of the seed.

The Mahāyānasaṃgraha gives a structurally identical answer from another angle. It says that "the right hearing-perfuming flowing forth from the supremely pure dharmadhātu" is the seed of the supramundane mind—the source is equal. But the same hearing-perfuming, in different practitioners, is divided into low, middle, and high grades:

From the low-grade perfuming the middle-grade arises; from the middle-grade the high-grade. Why? Because of the repeated cultivation of preparatory practice, hearing, reflection, and meditation.

The difference comes from "repeated preparatory cultivation"—the degree of accumulated practice. The same equal source, because of differences in the practitioner's diligence and orientation, appears as different "bodies" (the śrāvaka body, the pratyekabuddha body, the dharma-body).

The shared conclusion of the Awakening of Faith and the Mahāyānasaṃgraha is: the difference is functional—it comes from the thickness of nescience and the degree of perfuming, not from the category of the seed itself. The practical implication of this reading is: since the difference is functional, diligent cultivation can change the present state. No being is in principle shut out from becoming a buddha.

The ontological reading: Kuiji

Kuiji's explanation of "each receives its portion of the moisture" in the Fahua xuanzan is utterly different from that of the Awakening of Faith and the Mahāyānasaṃgraha. He reads it explicitly as ontological gotra:

The seeds of the five vehicles are substantially differentiated in their categories, as in "kinds many in number"... The three roots are fundamentally distinct, and from receiving the teaching they constitute the three vehicles.

Kuiji's argument rests on three pillars. First, Vasubandhu's antidote-formula in the Lotus Treatise explicitly marks "the Mahāyāna's unidirectional conceit—saying there is no separate two vehicles"—the very purpose of setting up the medicinal-herbs parable is to refute "no separate two vehicles"; reading it as functional gotra would weaken that antidote-purpose. Second, "the seeds of the five vehicles substantially differentiated in their categories" is an internal demand of Faxiang seed-doctrine—a seed-theory unable to uphold the five distinct gotras would compromise the internal consistency of the whole system. Third, Kuiji cites the Bodhisattva Stage Sūtra on "the agotra person, who is matured only by means of human and divine wholesome roots" as scriptural warrant—that there really exists a type of being with "no supramundane seeds."

In his verse-commentary, Kuiji maps the three grasses and two trees directly onto the five gotras: the small herb = the agotra, the two-vehicle gotra, and even the Mahāyāna gotra... the agotra person, granted only the pleasures of humans and gods, is named the small herb... the seven preparatory practices are the inferior, the two vehicles the middle herb, the bodhisattvas the superior herb... the great-herb category is divided in two: the pre-stages are the small tree, the ten stages the large tree. This is a dense mapping that binds every tier of the parable to an ontological gotra-doctrine.

Kuiji's reading is not a misreading; it is a legitimate operation within the system he stands in. Faxiang takes the seeds in the ālaya-vijñāna as the root cause of all manifestation, and the substantial differentiation of seed-categories is a foundational structure within that system. Where the functional reading of the Awakening of Faith and the Mahāyānasaṃgraha reads the medicinal-herbs parable as "describing differences in cultivation states," Kuiji reads it as "describing differences in inherent seeds." Both readings have textual warrant, both have śāstric support, both are internally coherent within their respective systems.

The position of this book here continues that of the previous chapter: present the divergence, do not pretend to dissolve it.

The two readings are in fact answering two different questions. The Awakening of Faith and the Mahāyānasaṃgraha answer: "What kind of difference can coexist on equal terms with buddha-nature?" The answer: functional difference. Kuiji answers: "Within the Yogācāra argumentative task, how do we account for the actual existence of the five vehicles in reality?" The answer: substantial seed-difference. The questions are different, so the answers are different—but this does not mean one of them is wrong.

A more refined possibility of integration runs like this: the Awakening of Faith and the Mahāyānasaṃgraha describe the equality face (all beings inherently possess suchness, and equally flow out hearing-perfuming), while Kuiji describes the difference face (in the actual phenomenon of the five vehicles, seed-categories really do differ). The two faces need not exclude each other—the Mahāyānasaṃgraha's twofold structure of "drawing in the indeterminate, intentionally teaching the one vehicle to the determinate" is precisely the embryonic form of this integration: the present functional state and the ultimate possibility can both be true at once.

But this book refuses to declare such an integration "the final answer." Hermeneutic divergence is itself a historical fact—different commentators, working on different argumentative tasks, gave legitimately different treatments of the same scripture. The work of this book is to present that divergence honestly, letting readers, according to their own present stage of practice and argumentative needs, choose the reading useful to them, rather than enthroning one system or forcing a reconciliation.

The two readings each serve a different therapeutic scene. The functional reading encourages the practitioner "not to regress"—since the difference comes from the degree of perfuming, diligent cultivation can change the present state. The ontological reading protects "the internal coherence of seed-doctrine"—since seeds have categorial differences, practice should first recognise one's own present state, then cultivate according to type. Both are skilful means.

Which Kind of Plant Are You?

Reading this far, a natural question floats up—which kind of plant am I?

This question is structurally the same as the previous chapter's "am I a determinate śrāvaka?" It can easily drag the reader into an anxious position—how am I to know whether I am a small herb or a large tree? Am I really only a small herb? And if I am only a small herb, what use am I?

The direction of this self-questioning is already mistaken.

The sūtra itself gives an extremely clear reply to this question: "only the Tathāgata sees them as they are." The judgement of capacity can be fully perceived only by the Buddha's omniscience—this is not our work. We have no reliable instrument for judging what capacity we are at present, still less an instrument for judging what that capacity will be several lifetimes from now.

But this is not an evasion of the form "we cannot know, so we need not think about it." What the sūtra really means is—you do not need to first judge what capacity you are before you can begin to practise. The rain has already fallen. It falls on the small herb, on the middle herb, on the small tree, on the large tree. The same one rain. Whichever kind of plant you are, you absorb in that kind of plant's way. This is not a problem to be solved first; it is a fact that grows clear in the course of practice.

A small herb is not a lesser existence than a large tree. It is the true manifestation of life standing at this present position. A small herb's work is to grow into the best a small herb can grow into—not to pretend it is a large tree. The thought "I ought to be a large tree" is exactly what would make the small herb wither—because it spends the energy the small herb was meant to use for growing on chasing a shape that does not, at present, belong to it.

⚠️ Here a misreading especially easy for modern readers must be corrected—reading the three grasses and two trees as a value-judgement, taking "small herb" as inferior and "large tree" as the valuable one. This reading mistakes the parable's descriptive function for a moral ranking. The verses say explicitly at the end: "All you śrāvakas—none of you have entered final extinction. What you practise is the bodhisattva path; gradually cultivating, all of you shall become buddhas"—every kind of plant is in the same one rain, every kind is covered by the same one promise. The difference is a difference of stage of growth, not a difference of worth in existence.

A misreading in the other direction must equally be corrected—"one rain moistens all = everyone naturally becomes a buddha, no effort needed." This reads the medicinal-herbs parable as a cheap promise and ignores the conditions. The Awakening of Faith left a very sharp simile to deal with this: "the fire-nature within wood is the right cause of fire; but if no one knows it and no expedient is employed, the fire cannot of itself burn the wood—there is no such case." The fire-nature within the wood is real, but without the expedient that kindles it, the wood will not burn of itself. What a herb needs in order to grow is not only the rain but also the soil, the sunlight, the warmth, the season—and likewise, what a being needs in order to become a buddha is not only the existence of the buddha-dharma but also its own diligence, the guidance of good spiritual friends, the accumulation of merit and resources. "All shall become buddhas" is an ultimate promise, not an immediate guarantee.

What the Medicinal Herbs Define "Embrace" to Mean

Having come this far, we can look back at the word "gathering-in" (攝) that the previous chapters have built.

Beginning with the burning-house parable, the first act of gathering-in is "to bring people out of the burning house"—to make those who do not know they are in the fire recognise their situation. Beginning with the prodigal-son parable, the second act of gathering-in is "to make the one who has recognised his situation recognise who he originally is"—to make the poor son who has hauled out the mire for twenty years recognise that he is the elder's son all along. The medicinal-herbs parable adds a third act—"to keep difference within difference, and at the same time build equality upon difference."

These three acts together make the true meaning of gathering-in show itself—to gathering-in is not to gather everything into a single thing, but to let everything, in its own original place, be borne at once by a larger whole. Only an gathering-in that can hold real difference avoids degenerating into the violence of homogenisation. Only a one vehicle that can preserve multiplicity is truly the one vehicle.

This is also the Lotus's true definition of "gathering the three and returning them to the one." To gather the three and return to the one is not to wipe three into one, but to keep the three in the positions of the three, while letting them converge within a larger structure. The one cloud's rain—the one; the three grasses and two trees each with their differences—the three; in accordance with their inherent nature each grows—the three not lost; all shall become buddhas—the return to the one. All four links are true at once.

The word "gathering-in" carries this weight—it neither flattens nor splits; it acknowledges difference, yet does not let difference turn into a chasm. This is one of the hardest things the Mahāyāna has to do, and exactly why the Lotus must use a full seven parables to demonstrate it over and over.

By this point, the triple cure formed by the Lotus's first three parables—burning house, prodigal son, medicinal herbs—is complete: curing the ordinary being who does not know the way out, curing the two vehicles who think they have reached the top, curing the bodhisattva who presses all difference flat. But there is still a question.

Since the difference in capacity is real—the medicinal-herbs parable has now established this—then might the expedient designed for a particular capacity in fact be a kind of deception? If a weary traveller needs to rest before he can walk on, and the guide conjures up a city for him to rest in, then tells him after his rest "this is not really the destination, the true treasure-place is still ahead"—has the guide cheated the traveller?

This question was handled once in the burning-house parable—the father promising three carts and giving the great cart, where the answer was the three-tier argument that "the expedient is not deception." But the burning-house parable's expedient is an expedient under emergency, brief in duration, its outcome revealed at once. The parable of the conjured city must handle a finer question—for a "provisional destination" offered over a long time to a particular capacity, once it is exposed as an expedient, does that stretch of rest still count as real practice?

The answer to this question is, among all the Lotus parables, the most moving of all.

The next chapter takes up the parable of the conjured city—the provisional nirvāṇa and the ultimate nirvāṇa.