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Re: [ontolog-forum] Looking forward at the past

To: "[ontolog-forum] " <ontolog-forum@xxxxxxxxxxxxxxxx>, "RK Stamper" <stamper.measur@xxxxxxxxx>
From: Pat Hayes <phayes@xxxxxxx>
Date: Mon, 6 Oct 2008 13:11:36 -0500
Message-id: <782B8E96-F2DC-4125-98CB-2FB00586B2FC@xxxxxxx>

On Oct 6, 2008, at 11:40 AM, RK Stamper wrote:

Dear Pat,


Yes, I do have an ontology that addresses the problems I raise.  Indeed it also leads to some interesting results in computing terms.


At its foundation is an ontology in the metaphysical sense, not in the Ontolog sense.  The core ideas will appear quite alien to the Ontolog community.  However, I shall try to explain but you must allow for the impossibility of my anticipating all the objections you might raise.


You and I may believe in an objective reality. But I emphasise that these are our separate beliefs.  Each of us can have direct knowledge of only the tiny fragment of reality existing in the individual's here and now.

Well, no, that is too strong. We can have knowledge of other times and places through many means. We can be looking (here, now) at an image of something which no longer exists and when it did, was a long way away. But perhaps your use of "direct" is meant to exclude such cases, in which case what you say is true but vacuous. 

Using signs (language, gestures, pictures etc.) that stand for the things known directly, we can extend our knowledge to embrace distant, past and future things.  Using signs is essentially social.

Language is inherently social, or has social roots. Its not clear that all our means of gaining information is essentially social, however. Photography isn't particularly social, for example.

Still confined to our individual here and nows, we each construct images of a 4-D world that we confidently treat as the one objective reality.  While "bounded in a nutshell" like Hamlet, each of us counts himself "a king of infinite space".  This amazing result depends upon our use of signs to form a society and share a composite view of the world. 

By taking our well-founded belief in an objective reality for granted, we fail to address the fundamental problem of how we have attained the wonderful result that Hamlet drew to our attention. Solipsism, despite its bad press, can help us find that explanation. 


James Gibson's Theory of Affordances provides an appropriate solipsistic account of direct knowledge. 

Maybe, but that certainly isn't what Gibson intended his theory to provide. His affordances are properties of the objective world, properties that are easily detected by the particular perceptual  abilities that have evolved to suit a species "niche". A key part of the Gibsonian program is that affordances can be computed from the actual world, and measured objectively. They are about as un-solipsistic as one can get. 

An organism perceives, not by recognising a given, ready-made, objective reality placed in the window of its senses, but by discovering, through direct action and experience, what repertoires of behaviour the world affords it. 

You are drawing a false contrast. "Discovering... affords it"  IS a process of recognizing objective reality placed in the window of the senses. Of course the percept is not fully determined by the reality alone: it is a function of the particular perceptual system. But that does not make it any the less a perception OF a single reality. 


ALL objects of perception are invariant repertoires of behaviour.


Directly perceived affordances are few compared with those we learn through indirect perceptions based on our collective, shared experiences.  These indirect perceptions depend on what we say to each other and the records and memories we keep.  All those linguistic and other signs also exist only in the present but they allow us to picture the past and future.


Ontologically speaking (metaphysical sense) reality consists of the affordances we recognise both individually and collectively.

No, that is a logical mistake (and a methodological one, if you wish to inherit the mantle of Gibson). All our knowledge of reality may consist of affordances (though this is already too strong), but that does not imply that reality itself so consists. In fact, that latter claim isn't internally coherent.

You will be wondering where this might take us technically, formally or computationally.  I shall not disappoint you.


Building on Gibson's work, we see that all knowledge of the world depends a) on an agent to do the knowing and b) the agent's behaviour that embodies the invariants we treat as perceived things. 

Whoa. Affordances (A la Gibson) are not embodied in behavior of the perceiver. They are computed properties of the perceived world. 

This suggests a syntax:

            agent affordance

            John upright

OK, but now tell us what this syntax means. What is being asserted here? That John is upright? If so, how does this differ from writing 

(upright John)

in Common Logic, or 

John rdf:type :upright .

in RDF?

Would it make sense to write, say, 

John John

? If not, why not (and can you state the syntactic constraint more generally)?

By realising or making available a repertoire of behaviour, the agent modifies itself

Please explain what you mean here. If it is the same agent, what does it mean to refer to it as "modified"?  Has some kind of change taken place? Is there an implicit time dimension, and should we think of these agents as continuants which endure through time but with changing properties? Etc.. All these are basic ontological questions you need to answer before proceeding. 

, so that recursively we can say:

            (agent affordance) affordance

            (John upright) jump

I no longer have any idea what this notation is supposed to mean. Jumping is usually something that is done by an agent. What is the agent here that is doing the jumping? (Is it John, or John-when-upright, or the uprightness of John (a trope, I imagine?), or ... what? What KIND of thing is it?)

Some affordances depend for their existence on two, coexisting antecedent affordances:

            (agent (affordance while affordance) ) affordance

            (John (paper while pencil)) draw

?? What does this mean? John draws with a pencil and paper? John sees a drawing done with pencil on paper? A drawing act with John as agent has pencil and paper as affordances? 

When we move from direct knowledge to knowledge shared by Society through the use of information, we need to treat Society as the root agent, for example:

            Society (person while person) marriage

            Society (John while Mary) marriage

But suppose they are not married; someone, perhaps John, can use a sign that stands for the marriage when he wants to propose:

Society (John, "(John, Mary) marriage" propose                 

where the quotes indicate that we are talking about a sign that stands for a marriage that does not yet exist, a sign that John employs to propose. 

Thus one builds...

I need a lot more detail and precision before setting out to build anything on this basis. Do you have a more detailed account of your notation and its intended meaning? 

Pat Hayes

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