--- title: "Meaning & Key Takeaway of: Program testing can be used to show the…" description: "\"Program testing can be used to show the presence of bugs, but never to show their absence!\" — Edsger Dijkstra" image: "https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png" --- # Program testing can be used to show the presence of bugs… ![“Program testing can be used to show the presence of bugs, but never to show their absence!” quote by Edsger Dijkstra](https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png) [Download](https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png) [Open image](https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png) > “Program testing can be used to show the presence of bugs, but never to show their absence!” [Edsger Dijkstra](https://sms4smile.com/quotes/author/edsger-dijkstra/) ## About This Quote This interpretation was drafted with AI assistance. It is one reading of the quote, not the author's own explanation. Testing can reveal bugs but can never prove their absence, highlighting limits of verification. **In simple terms:** Tests find bugs, not prove none. Key Takeaway Use testing alongside formal verification. Themes software quality testing limitations verification Mood analytical cautious Type technical philosophical When to use this quote - software development - quality assurance - project planning Key Concepts formal methods risk assessment Questions to Reflect On - How do you balance testing and verification? - What risks remain after testing? A Different Perspective Overreliance on testing may miss hidden defects. ★ ★ ★ ★ ★ No ratings yet [Absence](https://sms4smile.com/quotes/about/absence/) [Bugs](https://sms4smile.com/quotes/about/bugs/) [Programming](https://sms4smile.com/quotes/about/programming/) [Technology](https://sms4smile.com/quotes/about/technology/) ## Related quotes > [Never stop testing, and your advertising will never stop improving. Testing was used in advertising decades ago. 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Ambedkar](https://sms4smile.com/quotes/author/b-r-ambedkar/) [Browse all 2,057 Absence quotes ](https://sms4smile.com/quotes/about/absence/) ```json { "@context": "https://schema.org", "@graph": [ { "@type": "Quotation", "text": "Program testing can be used to show the presence of bugs, but never to show their absence!", "creator": { "@type": "Person", "name": "Edsger Dijkstra" }, "isPartOf": { "@id": "https://sms4smile.com/quotes/#website" }, "url": "https://sms4smile.com/quotes/edsger-dijkstra/program-testing-can-be-used-to-show-the-presence-of-bugs-but-never-to/", "about": { "@type": "Thing", "name": "Absence" }, "@id": "https://sms4smile.com/quotes/edsger-dijkstra/program-testing-can-be-used-to-show-the-presence-of-bugs-but-never-to/#quotation", "image": { "@type": "ImageObject", "@id": "https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png", "contentUrl": "https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png", "url": "https://sms4smile.com/quotes/i/fad/edsger-dijkstra-5102_absence_program-testing-can-be-used-to-show-the_2768472.png", "width": 1080, "height": 1080, "caption": "“Program testing can be used to show the presence of bugs, but never to show their absence!” — Edsger Dijkstra", "creditText": "SMS4Smile Quotes", "creator": { "@id": "https://sms4smile.com/quotes/#organization" } } }, { "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://sms4smile.com/" }, { "@type": "ListItem", "position": 2, "name": "Quotes", "item": "https://sms4smile.com/quotes/" }, { "@type": "ListItem", "position": 3, "name": "Edsger Dijkstra", "item": "https://sms4smile.com/quotes/author/edsger-dijkstra/" }, { "@type": "ListItem", "position": 4, "name": "Program testing can be used to...", "item": "https://sms4smile.com/quotes/edsger-dijkstra/program-testing-can-be-used-to-show-the-presence-of-bugs-but-never-to/" } ], "@id": "https://sms4smile.com/quotes/edsger-dijkstra/program-testing-can-be-used-to-show-the-presence-of-bugs-but-never-to/#breadcrumb" }, { "@type": "WebSite", "@id": "https://sms4smile.com/quotes/#website", "name": "SMS4Smile Quotes", "url": "https://sms4smile.com/quotes/", "publisher": { "@id": "https://sms4smile.com/quotes/#organization" } }, { "@type": "Organization", "@id": "https://sms4smile.com/quotes/#organization", "name": "SMS4Smile Quotes", "url": "https://sms4smile.com/quotes/", "logo": { "@type": "ImageObject", "url": "https://sms4smile.com/quotes/wp-content/themes/sq/assets/icons/icon-512.png", "width": 512, "height": 512 } } ] } ```