\documentclass[landscape]{slides}\usepackage{color}% .~/Desktop/slides/selfaware/selfaware1-sli.tex% /u/jmc/w04/asl  The abstract for this talk\begin{document}\begin{slide}  \begin{center}    \textcolor{red}{NONMONOTONIC REASONING---HISTORY AND REMARKS}  \end{center}    \begin{center}    John McCarthy, Stanford University \\    mccarthy@stanford.edu \\    http://www-formal.stanford.edu/jmc/ \\    \today  \end{center}  Nonmonotonic reasoning was needed for situation calculus.  \vfill\end{slide}%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%    \begin{slide}  \begin{center}    \textcolor{red}{PREHISTORY---NONMONOTONIC REASONING NOT TREATED EXPLICITLY}  \end{center}   Predicate completion---Keith ClarkClosed world assumption---ReiterMicroplanner---Sussman and WinogradProlog with negation as failure---ColmerauerGrumble about logic---Minsky\vfill\end{slide}%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\begin{slide}  \begin{center}    \textcolor{red}{HISTORY---NONMONOTONIC REASONING TREATED EXPLICITLY}  \end{center}    My 1977 paper had domain circumscription in it.  [Not the minimal model, but a minimal model.  Ashok Chandra pointed that out to me.]There was a workshop in 1978 at Stanford.1980 special issue of AIJ.$\bullet$ Non-monotonic logic---McDermott and Doyle$\bullet$ Logic of defaults---Reiter$\bullet$ Circumscription----McCarthyAuto-epistemic logic---Moore``Applications of circumscription to formalizing common sense''---McCarthy 1986The early history ends in 1986.Reiter's work on diagnosis.  McIlraith also.\vfill\end{slide}%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\begin{slide}  \begin{center}    \textcolor{red}{PREDICATE CIRCUMSCRIPTION---1986}  \end{center}    \begin{equation}\forall x.\lnot ab\ aspect1\ x \supset  \lnot flies\ x.% \leqno(\rm \ref{aiva})\end{equation}%% \label{a5}\begin{equation}\forall x.bird\ x \supset  ab\ aspect1\ x.% \leqno(\rm \ref{av})\end{equation}%\label{a6}\begin{equation}\forall x.bird\ x \land  \lnot ab\ aspect2\ x \supset flies\ x.% \leqno(\rm \ref{avi})\end{equation}%\label{a7}\begin{equation}    \forall x.ostrich\ x \supset  ab\ aspect2\ x.% \leqno(\rm \ref{avii})\end{equation}%% \label{a9}\begin{equation}\forall x.ostrich\ x \land  \lnot ab\ aspect3\ x \supset\lnot flies\ x.% \leqno(\rm \ref{aix})\end{equation}%$ostrich(Tim) \land bird(Tweety)$.Afterthought (2004): Need to circumscribe what can fly and what are birds and ostriches separately.\vfill\end{slide}%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\begin{slide}      \begin{center}    \textcolor{red}{USES OF NONMONOTONIC REASONING}  \end{center}1. As a communication convention.  Suppose  A  tells  B  abouta situation involving a bird.  If the bird cannot fly, and thisis relevant, then  A  mustsay so.  Whereas if the bird can fly, there isno requirement to mention the fact.        The proposed Common Business Communication Language (CBCL)(McCarthy 1982) must include nonmonotonic conventions about whatmay be inferred when a message leaves out such items as themethod of delivery.2. As a database or information storage convention.  It may be aconvention of a particular database that certain predicates havetheir minimal extension.3. As a rule of conjecture.4. As a representation of a policy.  The example is Doyle's ``The meetingwill be on Wednesday unless another decision is explicitly made''.5. As a very streamlined expression of probabilistic information whennumerical probabilities, especially conditional probabilities, areunobtainable.6. Auto-epistemic reasoning.  ``If I had an elder brother, I'd know it''.7. Both common sense physics and common sense psychology use nonmonotonicrules.  An object will continue in a straight line if nothing interfereswith it.  A person will eat when hungry unless something prevents it.    \vfill\end{slide}%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\begin{slide}  \begin{center}    \textcolor{red}{HUMAN NONMONOTONIC REASONING}  \end{center}  $\bullet$ Human reasoning compared to human speech.  In speech weskate at the edge of ambiguity.  That's why descriptive linguistics ishard.  Many ambiguities of speech are not reflected in a human'sinternal reasoning.  Van Benthem's students used circumscriptionto treat exhaustive sentences.$\bullet$ Most non-mathematical human reasoning is partly nonmmonotonic.$\bullet$ I arrived in Vancouver at 6:30 pm, \textcolor{red}{but}didn't leave for Whistler till 10 pm.  That was \textcolor{red}{because}the road was closed until midnight.  Is this the same as ``I wouldhave left earlier, \textcolor{red}{but} the road was closed.''$\bullet$ Is ``but'' just used in communication or should sentences with ``but'' be included in an AI systems internal knowledge base?$\bullet$ An argument: Taking into account only facts X, you jump to the conclusion that A, but if you also took into account facts Y, you would infer B.\vfill\end{slide}%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\begin{slide}    \begin{slide}  \begin{center}    \textcolor{red}{PART OF A DIFFERENT SPEECH}  \end{center}  $\bullet$ Computer scientists, through not paying attention to mathematical logic, are confused about many matters the logicians got right many decades ago.    $\bullet$ Ontology concerns what exists and does not include axioms.Common ontologies include individuals and unary predicates as objects but not relations as objects.  The hierarchies are unary.$\bullet$ The notation of first order logic is superior to the ad hocnotations that have been invented.  Decideable subsets of first orderlogic are readily designated.$\bullet$ XML isn't a language but a notation.  A language includesa set of predicate symbols that are intended to be given meaning.\vfill\end{slide}\end{document}I don't remember the extent to which my 1977 paper was responding to Minsky's remarks as a challenge, but I did use his example offlying and non-flying birds.domain circ.bird example7 kinds of nonmonotonic reasoningNonmonotonic human reasoning.  What strikes human attention is whena particular nonmonotonic reasoning step leads to error.Circumscription was used in linguistics to formalize exhaustive reasoning by two students of Johan van Benthem.The hard examples come from human speech tending to skate on thin ice---risking falling into ambiguity and even misunderstanding.A key word is ``but''.  ``But'' will be used in machine communication to cancel a nonmonotonic inference, but will it ever appear in a database for the machine's own use.*****************************