Alex, Your statement (from the end of your note) depends on what subject you're talking about. "Let me remind myself that the English language is formal at its core and for the language of communication between robots and people it is better to simply talk about simple English, etc." No. That depends entirely on the subject matter.. If your sentence is about mathematics, it can be translated very accurately to and from a mathematical formula. But if your statement is about what you see when you open your eyes, every word and phrase about the scene would be vague. Just consider the sentence "I see a blue jay drinking out of the birdbath." There is a continuous infinity of information in the image that you saw. No matter how long you keep describing the situation, a skilled artist could not draw or paint an accurate picture of what you saw. However, if the artist had a chance to look at the scene for just a few seconds, he or she could draw or paint an image that would be far more accurate than anything you could describe. That is just one short example of the difference between the discrete (and describable) and the continuous (and undescribable). Conclusion: An ontology of something that runs on digital computer can be specified precisely in English or Russian or any other natural language. But an ontology of the real world in all its continuous detail can never be expressed precisely in any language with a discrete set of words or symbols. John ---------------------------------------- From: "Alex Shkotin" <alex.shkotin(a)gmail.com> John, I am happy you agreed here: JFS:"Alex: "We need to formalize our scientific theories to use computers to their full potential." I agree,..." AS: And the next step is to just align our terminology: not necessarily use the same, but to understand used by other parts. JFS:"…but the formalization is ALWAYS context dependent. The engineering motto is fundamental: ALL THEORIES ARE WRONG, BUT SOME ARE USEFUL. That is true about formalization. It's only precise for subjects that can be expressed in finite bit strings. For 99.9% of all the information we get every second of our lives, vagueness is inescapable. We must deal with it by informal methods of approximations. Any formal statement is FALSE in general, but it may be useful when the limitations are made explicit. " AS: We do not use the term context when describing the situation in which the entity being studied is located (usually a system in some state and process). Usually it is described with what other systems and how it interacts and what happens on the border. Remotely acting forces are generally known: gravity and electromagnetic field. Of course we must take into account external flows of bodies, for example particles in the case of ISS. By the way, at the moment for some systems it is necessary to describe their information interaction. You can try to cover all this with the term context, but usually it seems that this is not used. But why not! I'll write more about finite bit strings later. In general: our robots must use formal language and algorithmic reasoning and acting. If they are boring we will have to endure it. Let me remind myself that the English language is formal at its core and for the language of communication between robots and people it is better to simply talk about simple English, etc. Alex