Science & Tech Quote by Edsger Dijkstra

Dijkstra’s line is a neat little demolition charge aimed at a popular category mistake: treating “thinking” as a natural kind that computers might either possess or fail to possess, like a soul hidden under the hood. By pairing “computer” with “submarine,” he forces the reader to hear how odd the original question sounds when you swap in a different engineered object. A submarine clearly moves through water, yet calling that “swimming” feels anthropomorphic, a metaphor smuggled in as a definition. The machine doesn’t fail at swimming; the word fails at precision.

The intent is less to dunk on AI than to police language and, by extension, intellectual standards. Dijkstra came out of a tradition in computer science that prized formal clarity over philosophical fog. In the mid-to-late 20th century, as “machine intelligence” became a public obsession (Turing tests, expert systems, sci-fi), the debate often slid into theater: grand pronouncements built on elastic verbs. Dijkstra’s quip warns that once you let metaphors do your thinking, you stop noticing what you’re not specifying - representation, reasoning, goals, error, explanation.

The subtext is a refusal to grant the debate its drama. Asking whether computers “think” invites a yes/no spectacle; asking what computations they perform, under what constraints, with what guarantees, is less glamorous but more real. Like much of Dijkstra, it’s an elitist kind of kindness: he’s saving you from an argument you can’t win because its terms were never stable to begin with.