虛 (Xū) — Empty

Say "shü," level. Five occurrences across five chapters, and four of them are a verb or an adjective.

Recommended: 虛 → "empty" (adjective), "to empty" (verb). (Never "emptiness," never "the void," never "vacuity," never "nothingness.") Chapter 16 is the one line still unsettled; see the close.

說文解字 (Shuōwén Jiězì, c. 100 CE): 大丘也。崐崘丘謂之崐崘虛。古者九夫爲井，四井爲邑，四邑爲丘。丘謂之虛。从丘虍聲。

"A great mound. The Kunlun mound is called the Kunlun 虛. In antiquity nine men's allotments made a 井 (jǐng — a well-field), four well-fields made a 邑 (yì — a settlement), four settlements made a 丘 (qiū — a mound). A 丘 is called 虛. From 丘 (qiū — mound), with 虍 (hū — tiger) for sound."

虛 is a unit of surveyed land. The dictionary does not reach for a void; it reaches for the well-field system and counts up from nine households. What makes a settlement-mound 虛 is that the people have gone — the sense later given its own graph, 墟 (xū — a ruin, an abandoned site).

So the picture is not boundless space. It is a bounded place that has been vacated: walls still standing, nobody home. Everything else in this entry follows from that.

The book uses it exactly that way, five times

Every occurrence is a container with its contents gone, and every container is a thing you could point at.

A heart. 虛其心，實其腹 — "empty their hearts, fill their bellies" (ch 3). 虛 is transitive here; it takes an object. 王弼 (Wáng Bì, d. 249 CE) makes the anatomy explicit: 心懷智而腹懷食，虛有智而實無知也 — "the heart harbors 智 (zhì — clever knowing) and the belly harbors food; empty what has 智, fill what has no 知 (zhī — knowing)." 河上公 (Héshàng Gōng, Han) gives the method: 除嗜欲去亂煩 — "remove craving and desire, cast off disorder and vexation."

A bellows. 天地之間，其猶橐籥乎？虛而不屈，動而愈出 — "between sky and earth, is it not like a bellows? Empty and never bent shut; the more it moves, the more comes out" (ch 5). 王弼: 橐排橐也，籥樂籥也。橐籥之中空洞無情無為，故虛而不得窮屈 — "橐 (tuó) is the blacksmith's bellows-bag, 籥 (yuè) is the musical pipe. Inside the bellows and the pipe it is 空洞 (kōng dòng — hollow and cavernous), without feeling, without doing; therefore it is empty and cannot be used up and bent shut." He defines 虛 by what is inside a made object.

Words. 豈虛言哉 — "were those empty words?" (ch 22). A saying with nothing in it.

A granary. 倉甚虛 — "the granaries are empty" (ch 53). The most carefully measured container an agrarian state owns, and the line is an indictment: the grain is gone because it was taken.

And its opposite is a full vessel. 盈 (yíng), 虛's antonym at chapters 4 and 45, is 說文 滿器也 — "a full vessel. From 皿 (mǐn — a vessel)." Vessel-language on both sides of the pair.

Why the noun is a Buddhist import

English emptiness is the standard rendering of śūnyatā, the central term of Mahāyāna Buddhist metaphysics — the doctrine that phenomena lack inherent existence. In Chinese that term is 空 (kōng — empty), and 虛空 (xū kōng) renders ākāśa, unbounded space.

空 does not occur in the Tao Te Ching. Not once, in eighty-one chapters.

Buddhism reaches China in roughly the first century CE; this text is Warring States, some four centuries earlier. So an English reader meeting emptiness here is handed a technical term from a tradition that had not yet arrived — and handed it in the one grammatical form, the abstract noun, that turns a description into a doctrine. It is the same failure as 一 (yī — one) rendered the One, which imports Neoplatonism, and 道 (dào) rendered the Way, which imports the missionaries.

It also imports the wrong physics. Śūnyatā is a claim that things have no self-standing essence. 虛 is a claim about a container: it has room in it. The bellows is not insubstantial. It is a made object with a hollow inside, and the hollow is what makes it work.

What is set aside

emptiness — the abstract noun, and śūnyatā's English. The adjective and the verb carry everything this book needs.

the void, vacuity — the void is already refused for 無 (wú — absence) in wu-you-無有.md, and it is worse here: 虛 is a hollow with walls, and a void has none. Vacuity additionally carries a slur in modern English that the Chinese does not.

nothingness — 虛 is never nothing. It is a something with room in it, which is the whole point of the bellows.

hollow — belongs to 窪 (wā — a low, sunken place) at chapter 22: 窪則盈, "be hollowed out, and be filled." Chapter 22 contains both 窪 and 虛, so this is precisely the distinction a forbidden: list cannot express — the checker gates on whether a character is present, and both are. It has to be held by the reader.

The working register

The tension, left open

Chapter 16 is the only place in the book where 虛 has to be a noun, and it is therefore the only place the Buddhist reading can get in. 致 (zhì — to send all the way there) 虛 (xū) 極 (jí — the far end) puts 虛 in the object slot, and English wants emptiness there.

The way out is to decline the noun and let 虛 be what it is in four lines out of five — a verb. Chapter 3's 虛其心 licenses the transitive directly, and 河上公 glosses chapter 16 the same way: 捐 (juān — shed) 情 (qíng — feeling) 去 (qù — cast off) 欲 (yù — desire)，五內 (wǔ nèi — the five viscera) 清 (qīng — clear) 淨 (jìng — still). What the object should be, and whether it may be supplied at all where the Chinese elides it, is undecided.

沖 (chōng) may not be an emptiness word at all. 說文 gives it as 涌搖也。从水、中 — "surging and shaking. From 水 (shuǐ — water) and 中 (zhōng — middle)," read like 動 (dòng — to move). Its empty sense at chapter 4's 道沖 depends on reading it as 盅 (zhōng — an empty vessel), a textual judgment sources/variants.yaml has not recorded either way. Water that surges and a vessel that is empty are not the same picture.

寥 (liáo — vast, unpeopled) at chapter 25 is a third word in the same field, and 說文 has no entry for it under any graph the importer can verify.