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Several references to the quote "There are only two hard things in Computer Science: cache invalidation and naming things" can be found, such as Martin Fowler's blog and others.

I'm unable to find the source of this quote, has he ever said it?

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Me, I'm interested in who came up with the variant: "There are only two hard things in Computer Science: cache invalidation, naming things, and off-by-one errors." – Doug Kavendek Mar 8 '14 at 5:15
Have you reached out to Netscape-ians? Phil was Principal Curmudgeon there.… – LIttle Ancient Forest Kami Nov 23 '14 at 18:17
I have this same question, and specifically, when did he say it? – DrZ214 Nov 24 '15 at 8:43
someone please post a huge bounty.... – Jason S Feb 17 at 17:45

Tim Bray says on Twitter:

Phil [Karlton] said it, I reported it, someone else added on the “off-by-one”.

Leon Bambrick replies that he added off-by-one.

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I'd like a little bit more than just one person saying he "reported it". Where did he report it? I found only which is dated 2005 but a google search for "cache invalidation and naming things" returns random results as far back as February 2001. – Vitor De Mario Jan 21 '15 at 21:27

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