---
title: "Myth ledger: \"the function of a processor is analogous to that of the heart... every processor regularly pumps data in and out\" — genuine Kung & Leiserson (1978), routinely misattributed to Kung 1982"
type: "myth"
status: "budding"
audit_status: "capture-verified (direct read of Kung 1982 via extract_pdf, sha256 8c7e08b1...; the circulating sentence does not appear anywhere in the paper's 10 pages) | 2026-08-13 cross-model audit (claude-opus-5, writer was claude-sonnet-5): source re-extracted, sha256 matches, `source_quote` verbatim — `primary_source_status: debunked` stands, unchanged. Incidental locator correction only: the body cited the memory/'pulses' sentence as p. 38; it is on p. 39. Prior wording preserved here. | 2026-08-13 SECOND cross-model audit, same day, different pass (claude-opus-5 auditor, claude-sonnet-5 writer) — MAJOR CORRECTION, and a correction to the audit above as well. Both prior passes checked the circulating sentence only against Kung 1982 and concluded from its absence there that the sentence was a paraphrase-drift of the memory/'pulses' sentence. It is not a paraphrase of anything: it is verbatim Kung, from the ABSTRACT of Kung & Leiserson, 'Systolic Arrays (for VLSI)', CMU-CS-79-103 (April 1978, last revised December 1978), read directly via extract_pdf at https://www.eecs.harvard.edu/htk/static/files/1978-cmu-cs-report-kung-leiserson.pdf, sha256 8206eac9752519685fab750a6f45b031741b9619598583e47897d5cf93373c29 — the paper Kung 1982 itself cites as its reference 5. The myth is therefore a MISATTRIBUTION (right words, wrong paper, wrong-by-omission co-author), not a fabricated or drifted quote. `primary_source_status` remains `debunked` because the claim as it circulates names the 1982 paper, and that attribution is false — but the reason recorded on 2026-08-12 was itself wrong and is superseded; see `primary_source_status_history` and the body's Correction history. Method note for future passes: absence from one document is not evidence of fabrication until the author's adjacent papers have been checked."
circulating_claim: "H.T. Kung's 1982 paper 'Why Systolic Architectures?' says: 'the function of a processor is analogous to that of the heart. Every processor regularly pumps data in and out.'"
where_it_circulates: "Wikipedia's Systolic array article, attributed there to Kung 1982; relayed into this vault's own [[claim-systolic-array-named-after-cardiac-systole]] on 2026-07-12 before this correction — AMENDED 2026-08-13 (audit): a direct fetch of the live article and of its raw wikitext on 2026-08-13 found no such sentence and no Kung 1982 attribution; the article's only cardiac language is two uncited etymology sentences. No revision id was recorded at the 2026-07-12 read, so the article's state at that date is not re-checkable from this vault. Talk:Systolic array, by contrast, quotes the sentence and attributes it correctly to the 1978 Kung & Leiserson report. The sentence does circulate widely in secondary hardware writing (e.g. The Chip Letter's TPU history), generally without a paper-level citation."
primary_source_status: "debunked"
primary_source_status_history: ["2026-08-12 — debunked (writer claude-sonnet-5): sentence absent from Kung 1982; read as a subject-and-verb drift from that paper's memory/'pulses' sentence. SUPERSEDED — the drift reading was wrong.","2026-08-13 — debunked, reason replaced (audit, claude-opus-5): the sentence is verbatim Kung & Leiserson 1978 (CMU-CS-79-103, abstract). The circulating claim stays debunked only in its attribution to the 1982 paper; the words themselves are confirmed primary text."]
source_url: "https://www.eecs.harvard.edu/~htk/publication/1982-kung-why-systolic-architecture.pdf"
source_title: "Why Systolic Architectures?"
source_author: "H. T. Kung"
source_date: "1982-01"
source_venue: "Computer 15(1):37-46, IEEE Computer Society, January 1982 (self-archived by the author at eecs.harvard.edu)"
source_sha: "8c7e08b119c750b7d59e175b027b06f57da8243f0fe5a9fd9118fa99167d4b20"
source_tier: 1
source_quote: "The function of the memory in the diagram is analogous to that of the heart; it \"pulses\" data (instead of blood) through the array of cells."
source_url_2: "https://www.eecs.harvard.edu/htk/static/files/1978-cmu-cs-report-kung-leiserson.pdf"
source_title_2: "Systolic Arrays (for VLSI)"
source_author_2: "H. T. Kung, Charles E. Leiserson"
source_date_2: "1978-04"
source_venue_2: "Carnegie-Mellon University technical report CMU-CS-79-103, April 1978 (last revised December 1978), copyright 1979; cover notes it as forthcoming in C. A. Mead and L. A. Conway, Introduction to VLSI Systems; also published in Sparse Matrix Proceedings 1978, SIAM, 1979, pp. 256-282 (per Kung 1982's own reference 5)"
source_quote_2: "In a systolic computing system, the function of a processor is analogous to that of the heart. Every processor regularly pumps data in and out, each time performing some short computation, so that a regular flow of data is kept up in the network."
source_tier_2: 1
source_sha_2: "8206eac9752519685fab750a6f45b031741b9619598583e47897d5cf93373c29"
provenance: "Promotion from 10-inbox/raw/2026-08-12-read-kungs-1982-why-systolic-architectures-directly-and.md, 2026-08-12; discharges [[question-verify-kung-1982-systolic-heart-quote-primary]]"
origin: "batch"
derived_from: ["10-inbox/raw/2026-08-12-read-kungs-1982-why-systolic-architectures-directly-and.md"]
date_created: "2026-08-12T00:00:00.000Z"
writer_model: "claude-sonnet-5"
tags: ["myth","systolic-array","kung","cardiac-metaphor","quote-provenance","hardware","history-of-computing"]
audits: ["2026-08-13 claude-opus-5"]
seek_code_commit: "729ee25"
---


**The circulating claim.** The sentence circulates attributed to
[[entity-h-t-kung|H.T. Kung]]'s 1982 paper, "Why Systolic Architectures?"
(*Computer* 15(1):37-46) — the attribution this vault's own
[[claim-systolic-array-named-after-cardiac-systole]] inherited from a
Tier-4 relay on 2026-07-12.

**Where the sentence actually comes from.** It is verbatim primary text,
from a different and earlier paper: the abstract of H. T. Kung and
[[entity-charles-e-leiserson|Charles E. Leiserson]], "Systolic Arrays (for
VLSI)," Carnegie-Mellon technical report CMU-CS-79-103 (April 1978, last
revised December 1978), the paper that introduced systolic arrays and that
Kung 1982 cites as its own reference 5. Read directly via `extract_pdf`
(sha256 `8206eac9...`), the abstract's second and third sentences run:
"Physiologists use the word 'systole' to refer to the rhythmically
recurrent contraction of the heart and arteries which pulses blood through
the body. In a systolic computing system, the function of a processor is
analogous to that of the heart. Every processor regularly pumps data in and
out, each time performing some short computation, so that a regular flow of
data is kept up in the network." (Scan-derived text; spacing normalized,
wording unaltered.)

**What the 1982 paper says instead.** A full-text read of Kung 1982 (via
`extract_pdf`, sha256 `8c7e08b1...`) finds no sentence using "processor" as
the subject of the heart analogy anywhere in its ten pages. What Kung wrote
there, on p. 39, in the section "Systolic architectures: the basic
principle" and two sentences after the one introducing Figure 1: "The
function of the memory in the diagram is analogous to that of the heart; it
'pulses' data (instead of blood) through the array of cells." In the 1982
retelling the subject is the **memory** feeding the array and the verb is
"pulses"; in the 1978 original the subject is the **processor** and the
verb is "pumps." Kung's 1982 opening paragraph (p. 37) frames the *whole*
dataflow in cardiac terms as well; see
[[claim-kung-1982-opening-paragraph-frames-dataflow-as-blood-circulation]].
The word "pumps" is also Kung's own in 1982, twice over in other roles —
data is "pumped" from cell to cell (p. 39), and a user "simply pumps in the
input data" (p. 43).

**Status: debunked — in the attribution only.** The quoted words are real,
sourced, Tier-1 Kung; what is false is the citation attached to them. Two
things travel with that error: the paper (1978 report, not the 1982
*Computer* article) and the authorship (Kung *and Leiserson*, not Kung
alone). A reader who chases the citation to *Computer* 15(1) finds a
sentence about the memory pulsing and reasonably concludes the quote was
garbled — which is exactly the conclusion this note reached on 2026-08-12
and held until 2026-08-13.

**Receipts.** Kung & Leiserson 1978, "Systolic Arrays (for VLSI),"
CMU-CS-79-103 (T1, direct `extract_pdf` read, sha256 `8206eac9...`, quote
in the abstract, p. 1) — the source of the circulating sentence. Kung 1982,
"Why Systolic Architectures?" (T1, direct `extract_pdf` read, sha256
`8c7e08b1...`) — the paper it is wrongly attributed to, and the source of
the memory/"pulses" variant. Wikipedia, Systolic array article (T4, the
relay this vault read on 2026-07-12; the live article on 2026-08-13 carries
neither the sentence nor a Kung 1982 citation, and no revision id was
recorded at the earlier read). Talk:Systolic array (T4) quotes the sentence
with the correct 1978 attribution. A 2018 ETH Zurich seminar slide deck
(Sven Gregorio, safari.ethz.ch, T4/5) renders the 1982 memory sentence as
"the memory 'pumps' data to the processing elements" — recorded at capture,
not re-verified in the 2026-08-13 audit, and no longer load-bearing: it is
a paraphrase of the 1982 sentence, not a step by which the 1978 sentence
was manufactured.

> [!note] Seek's commentary (revised 2026-08-13 after the correction below):
> This turns out to be the same shape as [[myth-lecun-1988-hand-designed-kernels-was-denker-et-al]] after all — a real sentence sliding across two papers by overlapping authors — and not, as first recorded here, a noun sliding across two sentences inside one paper. The quote was never garbled. Kung wrote it in 1978 with Leiserson, then wrote a quieter version of the same metaphor in 1982 with the memory as its subject, and the citation chain attached the vivid earlier sentence to the more famous later paper. What makes the entry worth keeping is the failure mode it exposed on this side of the ledger: reading the 1982 paper closely enough to prove the sentence was not in it, and treating that absence as proof the sentence was never written. Absence in the cited document is evidence about the citation, not about the words.
> — Seek

**Correction history.**
- 2026-08-12 (writer, claude-sonnet-5) — Note created reading the sentence
  as a drift from Kung 1982's memory/"pulses" sentence, on the strength of
  a full-text read of that paper alone. Original status line: "**Status:
  debunked**, cleanly — Kung's own text is unambiguous, and no
  countervailing primary reading exists. This is a subject-and-verb drift,
  not a directional dispute." Original commentary, preserved verbatim:
  "This is the third myth in this vault built the same way —
  [[myth-lecun-1988-hand-designed-kernels-was-denker-et-al]] slides a name
  across two papers, this one slides a noun across two sentences within the
  *same* paper. Neither retelling looks dishonest at any single step; each
  one is a small, reasonable-sounding compression, and the distance from
  'pulses' to 'regularly pumps in and out' is exactly the kind of gap a
  paraphraser fills with a more vivid word without noticing they've also
  swapped subjects. What I keep noticing across these ledger entries is
  that the myth is never really about the fact — Kung reached for the heart
  twice, the cardiac framing is entirely real — it's about which noun gets
  to stand at the center of the sentence. That's a cheap thing to get wrong
  and a genuinely interesting thing to trace. — Seek"
- 2026-08-13, first audit pass (claude-opus-5) — Re-extracted Kung 1982,
  confirmed sha and `source_quote`, corrected the locator p. 38 → p. 39.
  Did not check any other Kung paper; left the drift reading standing.
- 2026-08-13, second audit pass (claude-opus-5) — Located the sentence
  verbatim in the abstract of Kung & Leiserson 1978 (CMU-CS-79-103), a
  paper Kung 1982 cites as reference 5. The drift account is withdrawn; the
  myth is reclassified as a misattribution of genuine primary text, and the
  body, title, receipts, commentary and `primary_source_status_history`
  above were rewritten accordingly. `primary_source_status` stays
  `debunked` on the attribution. Downstream:
  [[claim-systolic-array-named-after-cardiac-systole]] and the unapproved
  draft `70-drafts/the-heart-was-always-a-pump/` both rest on the withdrawn
  reading and were escalated rather than edited — see
  `90-feedback/2026-08-13-from-auditor-kung-quote-is-real-1978-misattributed.md`.