How to Agree to Disagree - Video at ISWC 2022

Vídeo -> https://drive.google.com/file/d/1eQpa_VY7EpvPMUdQyvYNjdUrJdLLWIsc/view
 
How to Agree to Disagree
Managing Ontological Perspectives using Standpoint Logic

Lógica que acomoda diferentes pontos de vista
Segundo A ...
Segundo B ....

Como inferir se as visões de A e B forem conflitantes?

Standpoint logic bears some similarities to context logic in the style proposed by McCarthy and Buvac [19], which has also been applied in a description logic setting [15]. This tradition treats contexts as “first-class citizens” of the logic, i.e., full-fledged formal objects over which one can express first-order properties. In contrast, standpoint logic is suitable when a formalisation of the contexts involved is unfeasible, or when the interest resides in the content of the standpoints rather than the context in which they occur.
 
15. Klarman, S., Guti ́errez-Basulto, V.: Description logics of context. Journal of Logic and Com-
putation 26(3), 817–854 (2013)
 
19. McCarthy, J., Buvac, S.: Formalizing context (expanded notes). CSLI Lecture Notes 81, 13–
50 (1998)

Achei uma referência mais recente de McCarthy and Buvac (atualizada em 2012)

http://jmc.stanford.edu/articles/mccarthy-buvac-98/context.pdf

A second goal is to treat the context associated with a particular circumstance, e.g. the context of a conversation in which terms have particular meanings that they wouldn’t have in the language in general.

[poderia ser a circunstância em particular que uma alegação pode ser considerada útil e verdadeira]

The main formulas are sentences of the form
c′ : ist(c, p),
which are to be taken as assertions that the proposition p is true in the context c, itself asserted in an outer context c′....  For now, propositions may be identified with sentences in English or in various logical languages, but we may later take them in the sense of [38] as abstractions with possibly different identity conditions.

[p podem ser triplas]

2 Relations among Contexts

There are many useful relations among contexts and also context valued functions. Here are some.
1. specialize-time(t, c) is a context related to c in which the time is specialized to have the value t. We may have the relation c0 : ist(specialize-time(t, c), at(jmc, Stanford)) ≡ ist(c, at-time(t, at(jmc, Stanford))).
Here at-time(t, p) is the assertion that the proposition p holds at time t. We call this a lifting relation. It may be convenient to write at-time(t, foo(x, y, z)) rather than foo(x, y, z, t), because this lets us drop t in certain contexts. Many expressions are also better represented using modifiers expressed by functions rather than by using predicates and functions with many arguments. 

[Contexto Temporal]

3. There is a general relation specializes between contexts. We say specializes(c1, c2) when c2 involves no more assumptions than c1.

Human natural language risks ambiguity by not always specifying such assumptions, relying on the hearer or reader to guess what contexts makes sense. The hearer employs a principle of charity and chooses an interpretation that assumes the speaker is making sense. In AI usage we probably don’t usually want computers to make assertions that depend on principles of charity for their interpretation.

[Pessoas deduzem contexto implícito, e máquinas?]

5 Natural Deduction via Context

The formal theory of context can be used to represent inference and reason in the style of natural deduction. This requires lifting axioms (or lifting rules) to treat the context which a reasoning system is in as a formal object. If p is a sentence and we are in some context c, we define a new context assuming(c, p) so that it validates the following rules. 

6 Integrating Databases

We see the use of formalized contexts as one of the essential tools for reaching human level intelligence by logic based methods. However, formalized contexts have shorter term applications. In this section we deal with one short term application: we show how two data bases, which were not originally intended to be used together, can be integrated by lifting their contents into a wider context. We proceed with an example. For more practical issues involved in the task of integrating data and knowledge bases see [18, 21]

In order to reason with multiple databases, cps, an ad hoc context for reasoning about the particular problem, may be required. The problem solving context cps contains objects denoting the General Electric context cGE, the Navy context cN, and the Air Force context cAF. This enables us to talk about
facts which are contained in the corresponding databases. If for example the GE database contains a fact price(FX-22-engine) = $3600K then the sentence ist(cGE, price(FX-22-engine) = $3600K) is true in cps. Different data bases might make different assumptions. For instance, prices of engines in some contexts might or might not include spare parts or warranties. We need the ability to represent this information in cps. 

[Cada base de dados tem seu próprio contexto, isto é, regra para definir o cálculo do preço]

6.5 Existence as a Predicate

Not all objects will typically exist in all contexts. To deal with this phenomena, we introduce existence as a predicate, E (c, x). Intuitively, E (c, x) is true iff the object denoted by x exists in the context denoted by c.

11 Mental States as Outer Contexts

A person’s state of mind cannot be adequately regarded as the set of propositions that he believes—at least not if we regard the propositions as sentences that he would give as answers to questions.