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John Carmack on expert witnesses and 'non literal' copying

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Re: John Carmack on expert witnesses and 'non literal' copying

#161

Post by barrkel »

trendia wrote: post #33
barrkel wrote: post #27

Earlier quoted context omitted.

If you're genuinely mutating the AST, you'll end up with a different program that does something different or performs differently. There's only so many ways you can write a loop and they all look loop-like, whether it's for / while / do / tail recursion. But if you have a program that doesn't contain a loop at that point at all, or loops over something different, then you've got a different program.

You wouldn't literally mutate the AST, you would rewrite the code so that it performs the same output but using different code. Suppose there is a function y = f(x). You would write a different function g(x) such that g(x) = f(x) for every x, but such that the AST of g is different than the AST of f . You'd probably have to do this manually.

The same output with different code is what a clean room implementation would give you too. So clearly this is an insufficient specification.

Re: John Carmack on expert witnesses and 'non literal' copying

#162

Post by gregw2 »

It's kinda hard to square John's post-trial comments "I never tried to hide or wipe any evidence, and all of my data is accounted for, contrary to some stories being spread." with ZeniMax's post-trial comments at http://www.gameinformer.com/b/news/archive/2017/02/01/zenima... that " (vi) Carmack intentionally destroyed data on his computer after he got notice of this litigation and right after he researched on Google how to wipe a hard drive—and data on other Oculus computers and USB storage devices were similarly deleted (as determined by a court-appointed, independent expert in computer forensics); ... (viii) Carmack filed an affidavit which the court's expert said was false in denying the destruction of evidence; "

What is a reasonable explanation of this discrepancy? Varying notions of what consitutes "evidence"? Or differences in facts?

Re: John Carmack on expert witnesses and 'non literal' copying

#163

Post by barrkel »

noblethrasher wrote: post #93
barrkel wrote: post #27

Earlier quoted context omitted.

If you're genuinely mutating the AST, you'll end up with a different program that does something different or performs differently. There's only so many ways you can write a loop and they all look loop-like, whether it's for / while / do / tail recursion. But if you have a program that doesn't contain a loop at that point at all, or loops over something different, then you've got a different program.

> If you're genuinely mutating the AST, you'll end up with a different program that does something different or performs differently. If the original program was written in, say, F# and used a lot of pattern matching, then you could rewrite a straightforward moral equivalent in C# that used lots of visitors. Both the AST and IL will be substantially different, but the performance and functionality will be similar.

You're thinking at a much more concrete level than I am. When I think about an AST differ for the purpose of identifying copied code, I'd abstract out different ways of writing loops; I'd unify polymorphic calls to pattern matching; I'd break function call graphs down to a forest of basic blocks. In other words, I'd tune my AST comparison to actually look for algorithm similarity. I wouldn't be so trivially gamed.

Even better, I'd work with a traced execution, and examine isomorphisms between call graphs and data structures.

Re: John Carmack on expert witnesses and 'non literal' copying

#164

Post by hoorayimhelping »

>* After he had said he was “Absolutely certain there was non-literal copying” in several cases, I just wanted to shout “You lie!”. By the end, after seven cases of “absolutely certain”, I was wondering if gangsters had kidnapped his grandchildren and were holding them for ransom.*

This seems to be a very common reaction when reasonable people are put through a lawsuit.

Re: John Carmack on expert witnesses and 'non literal' copying

#165

Post by conanbatt »

addisonj wrote: post #10

I don't have the evidence so I can't make a judgement about whether Zenimax or Carmack is in the wrong here, but this does point out something strange in our court system and that is where a "jury of peers" which translates to normal people with little to no knowledge of the underlying subject matter. As our society becomes more specialized it seems a bit absurd to have people make judgements mostly based on how well…

If you judge a doctor with a jury by doctors, they wont convict. Its the blue wall of silence. The more related the jury is to the defendant, the less likely he is to get convicted.

Not to mention that the same bias you have could damage people. For example a doctor performing euthanasia might get compasion by most people, but disdain by the doctors that chose to never do such a thing.

There is no fair or justice, its not an objective value. Its a show we do because we know it keeps some people content, and some others fearful.

Re: John Carmack on expert witnesses and 'non literal' copying

#166

Post by arethuza »

justinlaster wrote: post #154
xamuel wrote: post #142

Earlier quoted context omitted.

>The judge was visibly surprised I would be too. What you said is rather arrogant. If you had based it on their having specific physics knowledge, that would be one thing. But to say that logic and reasoning is the exclusive realm of academia---that's very insulting to a lot of people.

Insulting. But doesn't make it any less true or false. To presume that your average joe has bothered to play in the realm of academic, diligent logic and reason is a mistake. I am not saying you need to go into a university, I'm not claiming a piece of paper will lend you credibility in this regard. It's about the time and effort that people spend practicing these subjects. How many people do you know outside of STEM…

Do we have evidence that STEMers are paragons of logical reasonable minded virtue outside of their particular domains?

Re: John Carmack on expert witnesses and 'non literal' copying

#167

Post by rayiner »

sokoloff wrote: post #137
rayiner wrote: post #75

Earlier quoted context omitted.

I think the Google v. Oracle example actually cuts against your theory. In that case, the jury found non-infringement on the patent claims, and literal infringement of portions of the code and API. The real question in that case was a legal one: whether the structure and organization of APIs was copyrightable. On appeal, the federal circuit found that it was, and remanded for a determination on Google's fair use defe…

Take Lego-branded building bricks. The functional aspects of the bricks (the sizes and tolerances of the pips) are not copyrightable. Being essential to their function, I am allowed to make competing bricks with interoperably-sized pips and voids. (I am of course prohibited from putting the Lego script on the pips or from marketing them as "Legos" or anything more than "compatible with Lego brand building bricks".) I…

The Lego example rests on the idea that you can't copyright a functional aspect of a design (because then copyright would impinge on the domain of patent). The interoperability angle there is incidental.

And applying that reasoning to code leads to the weird result that the "functional aspects" of all code (not just APIs) should not be copyrightable. Indeed, once we're talking about functionality instead of interoperability, there is an argument that APIs should be more protected than ordinary code. APIs by themselves don't do anything. They're creative, rather arbitrary designs.

Re: John Carmack on expert witnesses and 'non literal' copying

#168

Post by mememachine »

gregw2 wrote: post #162

It's kinda hard to square John's post-trial comments "I never tried to hide or wipe any evidence, and all of my data is accounted for, contrary to some stories being spread." with ZeniMax's post-trial comments at http://www.gameinformer.com/b/news/archive/2017/02/01/zenima... that " (vi) Carmack intentionally destroyed data on his computer after he got notice of this litigation and right after he researched on Google…

It looks like either someones lying or wrong

Re: John Carmack on expert witnesses and 'non literal' copying

#169

Post by justinlaster »

arethuza wrote: post #166
justinlaster wrote: post #154

Earlier quoted context omitted.

Insulting. But doesn't make it any less true or false. To presume that your average joe has bothered to play in the realm of academic, diligent logic and reason is a mistake. I am not saying you need to go into a university, I'm not claiming a piece of paper will lend you credibility in this regard. It's about the time and effort that people spend practicing these subjects. How many people do you know outside of STEM…

Do we have evidence that STEMers are paragons of logical reasonable minded virtue outside of their particular domains?

Science and technology would not be the fields that they are without such virtues. Your question is odd, the answer is kind of blatantly obvious.

I am not saying these people are infallible, I am saying that they are obviously equipped with better tooling and experience to make such judgements than someone who has no serious experience in dealing with "hard" subjects.

It was probably a mistake for me to explicitly list "STEM", but I thought it would hopefully convey my point a bit better. We live in an extremely technology oriented society, so it's a rather important subject to be decently versed in. However, a good, invested effort into the subject of philosophy would definitely be more than sufficient to make up for people's knowledge and reasoning errors.

Are we going to pretend this is not the case?

Re: John Carmack on expert witnesses and 'non literal' copying

#170

Post by intherdfield »

794CD01 wrote: post #123
intherdfield wrote: post #113

Earlier quoted context omitted.

Could you explain why you think this is a threat aimed at the expert witness in this trial? Any time someone publishes a work, they are putting their reputation at risk. If the work is bad, the whole world will know they did it. Carmack is saying he thinks this should be the case for reports and analyses given by expert witnesses.

You could say the same thing about anything people do in secret. Yet many people still want privacy.

> You could say the same thing about anything people do in secret.

I don't think that makes sense. There is no attempt to generalize this to things people do in secret. There is no claim that if something could risk your reputation then it follows that it should be made public.

Carmack's assertion is only that this particular work (for which the witness does voluntarily and is paid for) should be made public so that these witnesses use the same level of rigor they would for their other published work. And letting the public review it would have benefits too. (I am not agreeing or disagreeing with this.)

Ultimately, if we take Carmack's statements as true, it sounds to me like Facebook/Occulus' defense did not do an adequate job of instilling doubt in the report. He wrote that the defense did a technical tear down. I think if I was a juror, I would need to see this report completely destroyed. I'd need to see the same methodology applied to works where we know there was no copying and have it find false positives.

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