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ux266478yesterday at 3:42 PM2 repliesview on HN

Classical logic has plenty of limitations/roadblocks, all logics do. Logic isn't a unified domain, but an infinite beach of structural shards, each providing a unique lens of study.

Classical logic was rejected in computer science because the non-constructive nature made it inappropriate for an ostensibly constructive domain. Theoretical mathematics has plenty of uses to prove existences and then do nothing with the relevant object. A computer, generally, is more interested in performing operations over objects, which requires more than proving the object exists. Additionally, while you can implement evaluation of classical logic with a machine, it's extremely unwieldy and inefficient, and allows for a level of non-rigor that proves to be a massive footgun.


Replies

layer8yesterday at 4:33 PM

Classical logic isn’t rejected in computer science. Computer science papers don’t generally care if their proofs are non-constructive, just like in mathematics.

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zozbot234yesterday at 4:17 PM

But proving the object exists is still useful, of course: it effectively means you can assume an oracle that constructs this object without hitting any contradiction. Talking about oracles is useful in turn since it's a very general way of talking about side-conditions that might make something easier to construct.

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