if any pathway link is missing/false, the whole pathway is false. all the links have to be present/true for the pathway to be in effect/true
<div>-------- Original message --------</div><div>From: Ben Goertzel <b...@goertzel.org> </div><div>Date:07/08/2017 11:21 (GMT-08:00) </div><div>To: Linas Vepstas <linasveps...@gmail.com> </div><div>Cc: opencog <opencog@googlegroups.com>,Michael Duncan <mjsdun...@gmail.com> </div><div>Subject: Re: [opencog-dev] PartitionLink, biological pathways, human bodies, etc. </div><div> </div>OK I get that... but I don't see why it is appropriate for biological pathways... On Tue, Aug 8, 2017 at 2:19 AM, Linas Vepstas <linasveps...@gmail.com> wrote: > First, lets review SetLink: > > SetLink > ConceptNode "x" > ConceptNode "y" > ConceptNode "z" > > > EquivalenceLink > ConceptNode "last three letters of the alphabet" > SetLink > ConceptNode "x" > ConceptNode "y" > ConceptNode "z" > > > MemberLink > ConceptNode "x" > ConceptNode "last three letters of the alphabet" > MemberLink > ConceptNode "y" > ConceptNode "last three letters of the alphabet" > MemberLink > ConceptNode "z" > ConceptNode "last three letters of the alphabet" > > Again, with TV's: > > MemberLink <1.0> > ConceptNode "z" > ConceptNode "last letters of the alphabet" > MemberLink <0.9> > ConceptNode "w" > ConceptNode "last letters of the alphabet" > MemberLink <0.8> > ConceptNode "s" > ConceptNode "last letters of the alphabet" > MemberLink <0.2> > ConceptNode "m" > ConceptNode "last letters of the alphabet" > > > > Sooo .. AndMemberLink would be just like the above, except that whereever > you see SetLink above, you would have AndLink, and wherever you see > MmeberLink above, you would have AndMemeberLink. > > --linas > > > > > On Mon, Aug 7, 2017 at 1:11 PM, Ben Goertzel <b...@goertzel.org> wrote: >> >> I don't understand the proposed semantics of AndMemberLink, could you >> explain? >> >> >> >> On Sat, Aug 5, 2017 at 1:07 AM, Michael Duncan <mjsdun...@gmail.com> >> wrote: >> > i actually think an AndLink-like semantics better fits biochemical >> > pathways >> > at a computationally tractable level than partitions in that below the >> > level >> > of a whole organism, where one pathway ends and another begins is >> > largely >> > arbitrary. also, if one link is missing then the whole thing doesn't >> > work >> > but the last bit of a dead end might be the start of another path that >> > goes >> > to the same place, more like words and phrases that can be rearranged >> > and >> > swapped in different ways to say the same thing. linus idea of >> > AndMemberLinks and OrMemeberLinks would get around the size limitation >> > and >> > also seem like they would be useful for reasoning on moses models. >> > >> > On Monday, July 31, 2017 at 5:55:16 PM UTC-4, linas wrote: >> >> >> >> Hi Ben, Mike, >> >> >> >> >> >> On Fri, Jul 21, 2017 at 9:41 PM, Ben Goertzel <b...@goertzel.org> >> >> wrote: >> >>> >> >>> Some interesting representational issues have come up in the context >> >>> of Atomspace representation of pathways, which appear to have more >> >>> general implications… >> >>> >> >>> It seems the semantics we want for a biological pathway is sort of >> >>> like “the pathway P is a set of relationships R1, R2, …, R20” in kinda >> >>> the same sense that “the human body is a set of organs: brain, heart, >> >>> lungs, legs, etc.” >> >>> >> >>> First of all it seems what we have here is a part of relationship… >> >>> maybe >> >>> we want >> >>> >> >>> PartLink >> >>> ConceptNode “heart” >> >>> ConceptNode “human-body” >> >>> >> >>> and >> >>> >> >>> PartLink >> >>> >relationship< >> >>> >pathway< >> >>> >> >>> PartLink and PartOfLink have come and gone in >> >>> OpenCog/Novamente/Webmind history... >> >>> >> >>> An argument that PartLink should have fundamental status and a >> >>> well-defined fuzzy truth value is given in this paper: >> >>> >> >>> https://www.academia.edu/1016959/Fuzzy_mereology >> >>> >> >>> However what we need for biological pathways and human bodies seems >> >>> like a bit more. We want to say that a human body consists of a >> >>> certain set of parts... not just that each of them is a part... We're >> >>> doing a decomposition. >> >>> >> >>> One way to do this would be >> >>> >> >>> PartitionLink >> >>> ConceptNode “human-body” >> >>> ListLink >> >>> ConceptNode “legs” >> >>> ConceptNode “arms” >> >>> ConceptNode “brain” >> >>> etc. >> >>> >> >>> Relatedly, we could also have >> >> >> >> >> >> As mentioned earlier, there are several problems with this format. One >> >> is >> >> the "oops I forgot to mention xyz in the list" or "gosh I should have >> >> left >> >> out pqr" and this becomes a big problem: you have to delete the >> >> PartitionLink, delete the ListLink, create a new list and partition. >> >> In the >> >> meanwhile, some other subsystem might be holding a handle to the old, >> >> now-wrong PartitionLink, and there is no effective way of announcing >> >> "hey >> >> stop using that old thing, get my new thing now". >> >> >> >> A second problem is that the above doesn't have anywhere to hang >> >> addtional >> >> data: e.g. "legs are a big part of the human body, having a mas of >> >> nearly >> >> half of the body." You can't just slap that on as a (truth)value, cause >> >> there's no where to put that value. >> >> >> >> Third problem is that large list-links are hard to handle in the >> >> pattern >> >> matcher. Its much much harder to write a query of the form "find me >> >> all >> >> values of $X where >> >> >> >> PartitionLink >> >> ConceptNode “human-body” >> >> ListLink >> >> ConceptNode “legs” >> >> VariableNode “$X” >> >> ConceptNode “brain” >> >> >> >> because, ... well the ListLink is an ordrerd link, not an unordered >> >> link. >> >> If you forget to include the pqr (added above) then the search will >> >> fail. >> >> You could try to use unordered links and globnodes, but these lead to >> >> other >> >> difficulties, including the n! possible permutations of an unordered >> >> link >> >> become large n-factorial large when the unordered link has n items in >> >> it. >> >> Recall that old factorial-70 trick used to make calculators overflow. >> >> >> >> In general, any link with more than 3 or 4 or 5 items in it is bad >> >> news. >> >> This is a generic statement about knowledge representation in opencog. >> >> >> >> >> >>> OverlappingPartitionLink >> >>> C >> >>> L >> >>> >> >>> if we want to encompass cases where the partition elements in L can >> >>> overlap; or >> >>> >> >>> CoveringLink >> >>> C >> >>> L >> >>> >> >>> if we want to encompass cases where the partition elements in L can >> >>> overlap, AND the elements in L may encompass some stuff that’s not in >> >>> C >> >>> >> >>> For the pathway case, we could then say >> >>> >> >>> PartitionLink >> >>> ConceptNode “Krebs cycle” >> >>> ListLink >> >>> >relationship 1< >> >>> >relationship 2< >> >>> etc. >> >>> >> >>> >> >>> Now this solves the semantics problem but doesn’t solve the problem of >> >>> having a long ListLink…. A biological pathway might have 100s or >> >>> 1000s of relationships in it, and we don't usually want to make lists >> >>> that big in the Atomspace... >> >>> >> >>> To solve this we could do something like (for the human body case) >> >>> >> >>> PartitionLink >> >>> ConceptNode “human-body” >> >>> PartitionNode “body-partition-1” >> >>> >> >>> PartitionElementLink >> >>> PartitionNode “body-partition-1" >> >>> ConceptNode “legs” >> >>> >> >>> PartitionElementLink >> >>> PartitionNode “body-partition-1" >> >>> ConceptNode “arms” >> >>> >> >>> etc. >> >>> >> >>> and similarly (for the biological pathway case) >> >>> >> >>> PartitionLink >> >>> ConceptNode “Krebs cycle” >> >>> PartitionNode “krebs-partition-1” >> >>> >> >>> PartitionElementLink >> >>> PartitionNode “krebs-partition-1" >> >>> >relationship 1< >> >>> >> >>> PartitionElementLink >> >>> PartitionNode “krebs-partition-1” >> >>> >relationship 2< >> >> >> >> >> >> >> >> Yeah, sure. Not sure why the existing MemberLink is not sufficient for >> >> your purposes. The MemberLink has reasonably-well-defined semantics, >> >> there >> >> are already rules for handling it in PLN (or there will be rules -- I >> >> think >> >> its something Nil has thought about) I'm not clear on why you'd want >> >> to >> >> invent something that is just like MemberLink but is different. >> >> >> >>> >> >>> >> >>> ... >> >>> >> >>> There could be some nice truth value math regarding these, e.g. we >> >>> could introduce Ellerman's "logical entropy" which is really a >> >>> partition entropy. There are also connections with some recent >> >>> theoretical work I've been doing on "graphtropy" (using "distinction >> >>> graphs" that generalize partitions), which I'll post a paper on >> >>> sometime in the next week or two.... But that will be another email >> >>> for another day... >> >> >> >> >> >> Yeah graphical-entropy is something that I keep trying to work on, >> >> except >> >> that every new urgent disaster of the day distracts me from it. >> >> >> >> --linas >> >>> >> >>> >> >>> -- Ben >> >>> >> > -- >> > You received this message because you are subscribed to the Google >> > Groups >> > "opencog" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> > an >> > email to opencog+unsubscr...@googlegroups.com. >> > To post to this group, send email to opencog@googlegroups.com. >> > Visit this group at https://groups.google.com/group/opencog. >> > To view this discussion on the web visit >> > >> > https://groups.google.com/d/msgid/opencog/e1df7273-da14-45f5-8d0d-5ebad0d31217%40googlegroups.com. >> > >> > For more options, visit https://groups.google.com/d/optout. >> >> >> >> -- >> Ben Goertzel, PhD >> http://goertzel.org >> >> "I am God! I am nothing, I'm play, I am freedom, I am life. I am the >> boundary, I am the peak." -- Alexander Scriabin > > -- Ben Goertzel, PhD http://goertzel.org "I am God! I am nothing, I'm play, I am freedom, I am life. I am the boundary, I am the peak." -- Alexander Scriabin -- You received this message because you are subscribed to the Google Groups "opencog" group. To unsubscribe from this group and stop receiving emails from it, send an email to opencog+unsubscr...@googlegroups.com. To post to this group, send email to opencog@googlegroups.com. Visit this group at https://groups.google.com/group/opencog. To view this discussion on the web visit https://groups.google.com/d/msgid/opencog/j393fvlkp4nbwjl99mpwl0hu.1502135583490%40email.android.com. For more options, visit https://groups.google.com/d/optout.
