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Learn Prolog Now (2006)

lpn.swi-prolog.org

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Re: Learn Prolog Now (2006)

#191

Post by Woodi »

hunterpayne wrote: post #128
jodrellblank wrote: post #54

Earlier quoted context omitted.

> "4. Prolog is good at solving reasoning problems." Plain Prolog's way of solving reasoning problems is effectively: for person in [martha, brian, sarah, tyrone]: if timmy.parent == person: print "solved!" You hard code some options, write a logical condition with placeholders, and Prolog brute-forces every option in every placeholder. It doesn't do reasoning . Arguably it lets a human express reasoning problems bet…

Its a Horn clause resolver...that's exactly the kind of reasoning that LLMs are bad at. I have no idea how to graft Prolog to an LLM but if you can graft any programming language to it, you can graft Prolog more easily. Also, that you push Python and JavaScript makes me think you don't know many languages. Those are terrible languages to try to graft to anything. Just because you only know those 2 languages doesn't m…

> Its a Horn clause resolver...that's exactly the kind of reasoning that LLMs are bad at. I have no idea how to graft Prolog to an LLM but if you can graft any programming language to it, you can graft Prolog more easily.

By grafting LLM into Prolog and not other way around ?

Re: Learn Prolog Now (2006)

#192

Post by johnisgood »

jabbywocker wrote: post #167
johnisgood wrote: post #125

Earlier quoted context omitted.

Elaborate.

you don’t solve it by brute forcing possible solutions until one sticks

Yeah, read it in another comment. Why do you think doing calculations in your head is brute-forcing? Many people can do it flawlessly, without even knowing of these "tricks". They just know. Is that brute-force?

Re: Learn Prolog Now (2006)

#193

Post by ioma8 »

eatsleepmonad wrote: post #156

I recently implemented an eagerly evaluated embedded Prolog dialect in Dart for my game applications. I used SWI documentation extensively to figure out what to implement. But I think I had the most difficulty designing the interface between the logic code and Dart. I ended up with a way to add "Dart-defined relations", where you provide relations backed dynamically by your ECS or database. State stays in imperative…

Would you mind sharing your prolog dart lib?

Re: Learn Prolog Now (2006)

#194

Post by YeGoblynQueenne »

jodrellblank wrote: post #177
YeGoblynQueenne wrote: post #166

Earlier quoted context omitted.

>> You hard code some options, write a logical condition with placeholders, and Prolog brute-forces every option in every placeholder. It doesn't do reasoning. SLD-Resolution with unification (Prolog's automated theorem proving algorithm) is the polar opposite of brute force: as the proof proceeds, the cardinality of the set of possible answers [1] decreases monotonically. Unification itself is nothing but a dirty ha…

> " as the proof proceeds, the cardinality of the set of possible answers [1] decreases " In the sense that it cuts off part of the search tree where answers cannot be found? member(X, [1,2,3,4]), X > 5, slow_computation(X, 0.001). will never do the slow_computation - but if it did, it would come up with the same result. How is that the polar opposite of brute force, rather than an optimization of brute-force? If a l…

Rather, in the sense that during a Resolution-refutation proof, every time a new Resolution step is taken, the number of possible subsequent Resolution steps either gets smaller or stays the same (i.e. "decreases monotonically"). That's how we know for sure that if the proof is decidable there comes a point at which no more Resolution steps are left, and either the empty clause is all that remains, or some non-empty clause remains that cannot be reduced further by Resolution.

So basically Resolution gets rid of more and more irrelevant ...stuff as it goes. That's what I mean that it's "the polar opposite of brute force". Because it's actually pretty smart and it avoids doing the dumb thing of having to process all the things all the time before it can reach a conclusion.

Note that this is the case for Resolution, in the general sense, not just SLD-Resolution, so it does not depend on any particular search strategy.

I believe SLD-Resolution specifically (which is the kind of Resolution used in Prolog) goes much faster, first because it's "[L]inear" (i.e. in any Resolution step one clause must be one of the resolvents of the last step) and second because it's restricted to [D]efinite clauses and, as a result, there is only one resolvent at each new step and it's a single Horn goal so the search (of the SLD-Tree) branches in constant time.

Refs:

J. Alan Robinson, "A computer-oriented logic based on the Resolution principle" [1965 paper that introduced Resolution]

https://dl.acm.org/doi/10.1145/321250.321253

Robert Kowalski, "Predicate Logic as a Programming Language"

https://www.researchgate.net/publication/221330242_Predicate... [1974 paper that introduced SLD-Resolution]

Re: Learn Prolog Now (2006)

#195

Post by poulpy123 »

disambiguation wrote: post #40

I am once again shilling the idea that someone should find a way to glue Prolog and LLMs together for better reasoning agents. https://news.ycombinator.com/context?id=43948657 Thesis: 1. LLMs are bad at counting the number of r's in strawberry. 2. LLMs are good at writing code that counts letters in a string. 3. LLMs are bad at solving reasoning problems. 4. Prolog is good at solving reasoning problems. 5. ??? 6. LLM…

There are people working on integration deep learning with symbolic AI (but I don't know more)

Re: Learn Prolog Now (2006)

#196

Post by superdisk »

jodrellblank wrote: post #54
disambiguation wrote: post #40

I am once again shilling the idea that someone should find a way to glue Prolog and LLMs together for better reasoning agents. https://news.ycombinator.com/context?id=43948657 Thesis: 1. LLMs are bad at counting the number of r's in strawberry. 2. LLMs are good at writing code that counts letters in a string. 3. LLMs are bad at solving reasoning problems. 4. Prolog is good at solving reasoning problems. 5. ??? 6. LLM…

> "4. Prolog is good at solving reasoning problems." Plain Prolog's way of solving reasoning problems is effectively: for person in [martha, brian, sarah, tyrone]: if timmy.parent == person: print "solved!" You hard code some options, write a logical condition with placeholders, and Prolog brute-forces every option in every placeholder. It doesn't do reasoning . Arguably it lets a human express reasoning problems bet…

Contrary to what everyone else is saying, I think you're completely correct. Using it for AI or "reasoning" is a hopeless dead end, even if people wish otherwise. However I've found that Prolog is an excellent language for expressing certain types of problems in a very concise way, like parsers, compilers, and assemblers (and many more). The whole concept of using a predicate in different modes is actually very useful in a pragmatic way for a lot of problems.

When you add in the constraint solving extensions (CLP(Z) and CLP(B) and so on) it becomes even more powerful, since you can essentially mix vanilla Prolog code with solver tools.

Re: Learn Prolog Now (2006)

#197

Post by versteegen »

troupo wrote: post #143
nutjob2 wrote: post #119

Earlier quoted context omitted.

Your second sentence contradicts your first.

Pray tell how it contradicts the first. Just note: human pattern matching is not Haskell/Erlang/ML pattern matching. It doesn't go [1] through all possible matches of every possible combination of all available criteria [1] If it does, it's the most powerful computing device imaginable.

I 100% agree with nutjob :|

There are hundreds of trillions of synapses in the brain, and much of what they do (IANANS) could reasonably be described as pattern matching: mostly sitting idle waiting for patterns. (Since dendritic trees perform a lot of computation (for example, combining inputs at each branch), if you want to count the number of pattern matchers in the branch you can't just count neurons. A neuron can recognise more than one pattern.)

So yes, thanks to its insanely parallel architecture, the brain is also an insanely brute force pattern matcher, constantly matching against who knows how many trillions of previously seen patterns. (BTW IMHO this is why LLMs work so well)

(I do recognise the gap in my argument: are all those neurons actually receiving inputs to match against, or are they 'gated'? But we're really just arguing about semantics of applying "brute force", a CS term, to a neural architecture, where it has no definition.)

Re: Learn Prolog Now (2006)

#198

Post by victorbjorklund »

hunterpayne wrote: post #152
jm4 wrote: post #75

Earlier quoted context omitted.

It's been a while since I have done web dev, but web devs back then were certainly not scared of any language. Web devs are like the ultimate polyglots. Or at least they were. I was regularly bouncing around between a half dozen languages when I was doing pro web dev. It was web devs who popularized numerous different languages to begin with simply because delivering apps through a browser allowed us a wide variety o…

No web dev I have ever met could use Prolog well. I think your statement about web devs being polyglots is based upon the fact that web devs chase every industry fad. I think that has a lot to do with the nature and economics of web dev work (I'm not blaming the web devs for this). I mean the best way to succeed as a webdev is to write your own version of a framework that does the same thing as the last 10 frameworks…

That you haven’t met any webdevs using prolog probably is because 1) prolog is a very rare language among devs in general not just webdevs (unless you count people that did prolog in a course 20 years ago and remember nothing) 2) prolog just isn’t that focused on webdev (like saying ”not many embedded devs know react so I guess it is because react is too hard for them”)

Re: Learn Prolog Now (2006)

#199

Post by a96 »

jackallis wrote: post #3

is prolog a use-case language or is it as versatile as python?

It's a language that should have just been a library. There's nothing noteworthy about it and it's implementable in any working language. Sometimes quite neatly. Schelog is a famous example.
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