--- title: Casey Muratori – The Root of The Root of All Evil – BSC 2026 description: A conference talk traces the true origin and context of the phrase "premature optimization is the root of all evil," first published by Donald Knuth in a 1974... canonical: https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Casey Muratori – The Root of The Root of All Evil – BSC 2026 | daily.dev og:description: A conference talk traces the true origin and context of the phrase "premature optimization is the root of all evil," first published by Donald Knuth in a 1974... og:url: https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl og:image: https://api.daily.dev/og/posts/sfItKcVhL.png og:image:alt: Casey Muratori – The Root of The Root of All Evil – BSC 2026 og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Casey Muratori – The Root of The Root of All Evil – BSC 2026 **[Lobsters](https://daily.dev/sources/lobsters)** · 170 min read · 0 upvotes · 0 comments ## Summary A conference talk traces the true origin and context of the phrase "premature optimization is the root of all evil," first published by Donald Knuth in a 1974 ACM article. It untangles a decades-old attribution dispute involving Knuth, Tony Hoare, and Edsger Dijkstra, then dives into the historical backdrop: Dijkstra's 1968 "Go To Statement Considered Harmful" letter (a title given by editor Niklaus Wirth, not Dijkstra himself), the software crisis debated at the 1968 NATO conference, Dijkstra's depression and recovery through writing "Notes on Structured Programming," and Tony Hoare's disastrous Elliott 503 Mark II ALGOL compiler project that saw compile speed crash from ~1000 characters/second to just 2 characters/second due to unplanned memory allocation and thrashing. The talk argues that understanding this tangled history changes how the famous optimization quote should be interpreted. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Where does the phrase premature optimization is the root of all evil actually come from? It comes from Donald Knuth's 1974 paper Structured Programming with Go To Statements, published in Computing Surveys volume six. Knuth wrote it again in 1989 in a paper called The Errors of TeX, where he attributed it as a 'dictum,' fueling later speculation that Tony Hoare or Edsger Dijkstra may have originated it, though no definitive earlier source has been confirmed. _Anyone citing this famous quote in a performance debate can trace the sourcing details on daily.dev._ ### What is the actual data behind Knuth's claim that 3% of a program accounts for 90% of its runtime? Knuth's 1974 paper cites two references for the claim that most runtime concentrates in about 3% of source text, but the only traceable source, Dan Ingalls' Fortran profiling study cited in Knuth's own 1971 empirical study of Fortran programs, actually shows that 3% of code accounts for roughly 50% of runtime, not 90%, and the most expensive routine in a sample program only reached 66.7%. The stronger 90% framing appears to be an unsupported rhetorical overstatement. _Developers weighing when optimization actually pays off can dig into the sourcing on daily.dev._ ### What did Tony Hoare's Elliott 503 Mark II Algol compiler project reveal about early software performance problems? Tony Hoare's team shipped a new Algol compiler that ran at only two characters per second, down from the 500-1000 characters per second of their earlier compiler, due to a failure to plan main storage allocation, causing severe virtual memory thrashing. After months of work they improved it to eight characters per second, a fourfold gain that was still commercially unusable, and the project was ultimately canceled. _Teams debugging severe performance regressions can trace this early cautionary case study on daily.dev._ ## Similar posts on daily.dev - [Casey Muratori: Surprises In Computer History And Where Bad Code Comes From](https://daily.dev/posts/casey-muratori-surprises-in-computer-history-and-where-bad-code-comes-from-htya9hnlf) · The Developing Dev · 12 upvotes · 0 comments - [\(comic\) Premature optimization](https://daily.dev/posts/comic-premature-optimization-0vkeatycy) · Work Chronicles · 23 upvotes · 0 comments --- Tags: [#performance](https://daily.dev/tags/performance) [View this post on daily.dev](https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Casey Muratori – The Root of The Root of All Evil – BSC 2026","url":"https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl"},"datePublished":"2026-08-26T12:59:43.638Z","dateModified":"2026-09-14T08:51:18.231Z","description":"A conference talk traces the true origin and context of the phrase \"premature optimization is the root of all evil,\" first published by Donald Knuth in a 1974...","image":"https://i.ytimg.com/vi/hpj6r6CjJf8/sddefault.jpg","thumbnailUrl":"https://i.ytimg.com/vi/hpj6r6CjJf8/sddefault.jpg","isAccessibleForFree":true,"articleSection":"Lobsters","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Lobsters","logo":"https://media.daily.dev/image/upload/s--tl8v_Fku--/f_auto,t_logo/v1698841318/logos/lobste.jpg","url":"https://daily.dev/sources/lobsters"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"performance","timeRequired":"PT170M","video":{"@type":"VideoObject","name":"Casey Muratori – The Root of The Root of All Evil – BSC 2026","description":"A conference talk traces the true origin and context of the phrase \"premature optimization is the root of all evil,\" first published by Donald Knuth in a 1974...","thumbnailUrl":"https://i.ytimg.com/vi/hpj6r6CjJf8/sddefault.jpg","uploadDate":"2026-08-26T12:59:43.638Z","duration":"PT170M","url":"https://api.daily.dev/r/sfItKcVhL","embedUrl":"https://www.youtube.com/embed/hpj6r6CjJf8"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Lobsters","item":"https://daily.dev/sources/lobsters"},{"@type":"ListItem","position":3,"name":"Casey Muratori – The Root of The Root of All Evil – BSC 2026"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/casey-muratori-the-root-of-the-root-of-all-evil-bsc-2026-sfitkcvhl#faq","mainEntity":[{"@type":"Question","name":"Where does the phrase premature optimization is the root of all evil actually come from?","acceptedAnswer":{"@type":"Answer","text":"It comes from Donald Knuth's 1974 paper Structured Programming with Go To Statements, published in Computing Surveys volume six. 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