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      <title-group>
        <article-title>Deontic Counteridenticals and the Design of Ethically Correct Intelligent Agents: First Steps1</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Selmer Bringsjord Rikhiya Ghosh Rensselaer AI</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Reasoning (RAIR) Lab</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>James Payne-Joyce RPI Troy NY</string-name>
        </contrib>
      </contrib-group>
      <abstract>
        <p>Counteridenticals, as a sub-class of counterfactuals, have been briefly noted, and even briefly discussed, by some thinkers. But counteridenticals of an “ethical” sort apparently haven't been analyzed to speak of, let alone formalized. This state-of-affairs may be quite unfortunate, because deontic counteridenticals may well be the key part of a new way to rapidly and wisely design ethically correct autonomous artificial intelligent agents (AAIAs). We provide a propaedeutic discussion and demonstration of this design strategy (which is at odds with the strategy our own lab has heretofore followed in ethical control), one involving AAIAs in our lab.</p>
      </abstract>
    </article-meta>
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  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        If you were an assassin for the Cosa Nostra, you would be
obligated to leave your line of work. The previous sentence (very likely
true, presumably) is what to our knowledge is a rare type of
counteridentical statement that has received scant attention: viz., a
deontic counteridentical. Counteridenticals simpliciter, as a sub-class of
counterfactuals, have been briefly noted, and even briefly discussed,
by some thinkers. But counteridenticals of an “ethical” sort
apparently haven’t been rigorously analyzed, let alone formalized. This
state-of-affairs may be quite unfortunate, because deontic
counteridenticals may well be the linchpin of a new way to rapidly and wisely
design ethically correct autonomous artificial intelligent agents
(AAIAs). For example, what if AAIA2, seeing the lauded ethically
correct conduct of AAIA1 in context c, reasons to itself, when later in
c as well: “If I were AAIA1, I would be obligated to refrain from
doing . Hence I will not do .” The idea here is that is a
forbidden action, and that AAIA2 has quickly learned that it is indeed
forbidden, by somehow appropriating to itself the “ethical nature”
of AAIA1. We provide a propaedeutic discussion and demonstration
of this design strategy, one involving AAIAs in our lab. This design
strategy for ethical control is intended to be much more efficient than
the more laborious, painstaking logic-based approach our lab has
followed in the past; but on the other hand, as will become clear, this
approach relies heavily not only formal computational logic, but on
computational linguistics for crucial contributions.
Counteridenticals have been defined in different ways by
philosophers and linguists; most of these ways define a large area of
intersection in terms of what should count as a counteridentical. A broader
and inclusive way is given by
        <xref ref-type="bibr" rid="ref22">Waller et al. (2013)</xref>
        , who describes
them as “statements concerning a named or definitely described
individual where the protasis falsifies one of his properties.” Protasis
1 We are indebted, immeasurably, to ONR and AFOSR for funding that has
enabled the inauguration, described herein, of r&amp;d in the ethical control
artificial intelligent agents via deontic counteridenticals.
here refers to the traditional grammatical sense of the subordinate
clause of a conditional sentence. By this definition, a sentence like
“If the defendant had driven with ordinary care, the plaintiff would
not have sustained injury” would be treated as a counteridentical.
However, though a counteridentical sense can be attributed to such a
statement, the two agents/entities in question are not really identified.
(This is therefore classifed by us as shallow counteridentical.)
Counteridenticals are hence described mostly as counterfactuals where the
antecedent (= the leftside “if” part) involves comparison of two
incompatible entities within the purview of a “deep” pragmatic
interpretation; these we classify as deep counteridenticals. A similar
definition of counteridenticals is given by
        <xref ref-type="bibr" rid="ref21">Sharpe (1971)</xref>
        , who requires
an individual to turn into a numerically different individual for the
protasis to be true in a subjunctive conditional. With the purpose of
exploring scenarios in which the protasis can hold, this paper delves
into possibilities of a de jure change of identities to finally conclude
that counteridenticals are more pragmatic in sense than other types
of counterfactuals. Pollock (1976) agrees with the above depiction
— but he stresses the equivalence of the identities in the antecedent.
For the purpose of this paper, we affirm the generally accepted
definition and use Pollock’s refinement to arrive at our classification of
counteridenticals.
3
      </p>
    </sec>
    <sec id="sec-2">
      <title>Some Prior Work on Counteridenticals</title>
      <p>Precious little has been written about counteridenticals. What
coverage there is has largely been within the same breath as discussion
of counterfactuals; therefore, treatment has primarily been associated
with the principles governing counterfactuals that apply to
counteridenticals at large. Dedicated investigation of counteridenticals that
have deep semantic or pragmatic importance has only been hinted at.
Nonetheless, we now quickly summarize prior work.
3.1</p>
    </sec>
    <sec id="sec-3">
      <title>Pollock</title>
      <p>
        Pollock (1976) introduces counteridenticals when he discusses the
pragmatic ambiguity of subjunctives, as proposed by
        <xref ref-type="bibr" rid="ref14">Chisholm
(1955)</xref>
        . However, contra Chisholm, Pollock argues that this
ambiguity owes its origin to ambiguities in natural languages. He also points
out that a true counteridentical must express the outright equivalence
of the two entities in its antecedent, and not merely require an
atomistic intersection of their adventitious properties for the protasis to
hold. He introduces subject reference in analyzing counteridenticals
and distinguishes between preferred subject conditionals and
simple subjunctive conditionals. If the antecedent form is “If A were B,”
whether the consequent affects A or B determines whether the
overall locution is of the simple subjunctive type or the preferred subject
type. Although we do not concur with Pollock’s rather rigid
definitions or subscribe entirely to his classification scheme, his thinking
informs our system for classifying deontic counteridenticals: we
follow him in distinguishing in our formulae between those that make
only casual reference to A being B, versus cases where A is B.
3.2
      </p>
    </sec>
    <sec id="sec-4">
      <title>Declerck and Reed</title>
      <p>
        <xref ref-type="bibr" rid="ref15">Declerck &amp; Reed’s (2001)</xref>
        treatment of counteridenticals touches
upon some important aspects of their semantic interpretation, which
leverages syntactic elements. Through discussion of speaker deixis,
their work explores co-reference resolution and hints at the role of
the speaker in pragmatic resolution of a counteridentical. There are
powerful observations in
        <xref ref-type="bibr" rid="ref15">(Declerck &amp; Reed 2001)</xref>
        on extraction of
temporal information from a counteridentical. In addition, a basic
sense of the purpose and mood of a sentence can also be gleaned
from the verb form in the statement in their approach, and we have
used this in our own algorithm for detecting deontic counterfactuals.
3.3
      </p>
    </sec>
    <sec id="sec-5">
      <title>In Economics</title>
      <p>
        We suspect the majority of our readers will be surprised to learn that
the concepts underlying counteridenticals are quite important in
economics, at least in some sub-fields thereof. This is made clear in
elegant and insightful fashion by
        <xref ref-type="bibr" rid="ref1">Adler (2014)</xref>
        . The kernel of the
centrality of counteridenticals in some parts of economics is that
interpersonal measurement of utility and preferences presupposes such
notions that if A were B, A would, like B, prefer or value some
type of state-of-affairs in a particular way. In short, economics
often assumes that rational agents can “put themselves in every other
agent’s shoes.” After
        <xref ref-type="bibr" rid="ref1">Adler (2014)</xref>
        points this out, he rejects as too
difficult the project of formalizing counteridenticals, and proposes an
approach that ignores them. Our attitude is the exact opposite, since
we seek to formalize and implement reasoning about and over
counteridenticals, by AAIAs.
3.4
      </p>
    </sec>
    <sec id="sec-6">
      <title>Other Treatments</title>
      <p>Paul Meehl asks a penetrating question that aligns with our
reluctance to fully adopt Pollock’s definition of counteridenticals: Which
properties of compared entities should be considered for the
statement in question to be true? He devises a modified possible-world
model called world-family concept which, assisted by exclusion
rules that avoid paradoxical metaphysics, can result in a good set
of such properties.
4</p>
    </sec>
    <sec id="sec-7">
      <title>Prior RAIR-Lab Approach to Ethical Control</title>
      <p>
        Hitherto, Bringsjord-led work on machine/robot ethics has been
unwaveringly logicist
        <xref ref-type="bibr" rid="ref18">(e.g., see Govindarajulu &amp; Bringsjord 2015)</xref>
        ; this
ethos follows an approach he has long set for human-level AI (e.g.,
see Bringsjord &amp; Ferrucci 1998, Bringsjord 2008b) and its sister
field computational cognitive modeling (e.g., see Bringsjord 2008a).
In fact, the basic approach of using computational formal logic to
ensure ethically controlled AAIAs can be traced back, in the case
of Bringsjord and collaborators, to
        <xref ref-type="bibr" rid="ref2">(Arkoudas, Bringsjord &amp; Bello
2005, Bringsjord, Arkoudas &amp; Bello 2006)</xref>
        . Recently, Bringsjord has
defined a new ethical hierarchy EH for both persons and machines
that expands the logic-rooted approach to the ethical control of
AAIAs
        <xref ref-type="bibr" rid="ref18">(Bringsjord 2015)</xref>
        . This hierarchy is distinguished by the fact
that it expands the basic categories for moral principles from the
traditional triad of forbidden, morally neutral, and obligatory, to
include four additional categories: two sub-ones within supererogatory
behavior, and two within suberogatory behavior. EH reveals that
the logics invented and implemented thus far in the logicist vein of
Bringsjord and collaborators (e.g., deontic cognitive event calculi,
or DeCE C)
        <xref ref-type="bibr" rid="ref11">(Bringsjord &amp; Govindarajulu 2013)</xref>
        , are inadequate. For
it can be seen that for instance that specification of DeCE C, shown
in Figure 1, contains no provision for the super/suberogatory, since
the only available ethical operator is O for obligatory.
      </p>
      <sec id="sec-7-1">
        <title>Syntax Rules of Inference</title>
        <p>S ::= OMbojmecetn|t A|gBeonotle|aSne|lfF@lueAngte|nNtu|mAectriiocnType | Action v Event | C(tC, P(t(,af,)t,tf  ) !t1 .K..(ta,t,tfn)) [R1] C(t,K(a,t,f ) ! B(a,t,f )) [R2]
K(a1,t1,...K(an,tn,f )...) [R3] K(af,t,f ) [R4]
action : Agent⇥ ActionType ! Action
initially : Fluent ! Boolean
holds : Fluent⇥ Moment ! Boolean
happens : Event⇥ Moment ! Boolean
clipped : Moment⇥ Fluent⇥ Moment ! Boolean
f ::= initiates : Event⇥ Fluent⇥ Moment ! Boolean
terminates : Event⇥ Fluent⇥ Moment ! Boolean
prior : Moment⇥ Moment ! Boolean
interval : Moment⇥ Boolean
⇤ : Agent ! Self
payoff : Agent⇥ ActionType⇥ Moment ! Numeric
t ::= x : S | c : S | f(t1,...,tn)
t : Boolean | ¬f | f ^ y | f _ y | 8 x : S. f | 9 x : S. f</p>
        <p>P(a,t,f ) | K(a,t,f ) | C(t,f ) | S(a,b,t,f ) | S(a,t,f )
f ::= B(a,t,f ) | D(a,t,holds(f,t0)) | I(a,t,happens(action(a⇤ ,a ),t0))</p>
        <p>O(a,t,f ,happens(action(a⇤ ,a ),t0))</p>
        <p>C(t,K(a,t1,f 1 ! f 2) ! K(a,t2,f 1) ! K(a,t3,f 3)) [R5]
C(t,B(a,t1,f 1 ! f 2) ! B(a,t2,f 1) ! B(a,t3,f 3)) [R6]
C(t,C(t1,f 1 ! f 2) ! C(t2,f 1) ! C(t3,f 3)) [R7]
C(t,8 x. f ! f [x 7! t]) [R8] C(t,f 1 $ f 2 ! ¬f 2 ! ¬f 1) [R9]
C(t,[f 1 ^ ...^ f n ! f ] ! [f 1 ! ... ! f n ! y ]) [R10]
B(a,t,f ) B(a,t,f ! y ) [R11a] B(a,t,f ) B(a,t,y ) [R11b]</p>
        <p>B(a,t,y ) B(a,t,y ^ f )
S(s,h,t,f )
B(h,t,B(s,t,f )) [R12]
IP((aa,,tt,,hhaappppeennss((aacctitoionn((aa⇤⇤ ,,aa )),,tt0)))) [R13]
B(a,t,f ) B(a,t,O(a⇤ ,t,f ,happens(action(a⇤ ,a ),t0)))
O(a,t,f ,happens(action(a⇤ ,a ),t0))</p>
        <p>K(a,t,I(a⇤ ,t,happens(action(a⇤ ,a ),t0)))</p>
        <p>f $ y
O(a,t,f ,g ) $ O(a,t,y ,g ) [R15]
[R14]
In the new logic corresponding to EH , LEH , some welcome
theorems are not possible in DeCE C. For example, it’s provable in
LEH that superogatory/suberogatory actions for agent aren’t
obligatory/forbidden. Importantly, LEH is an inductive logic, not a
deductive one. Quantification in LEH isn’t restricted to just the standard
pair 98 of quantifiers in standard extensional n-order logic: EH is
based on three additional quantifiers (few, most, vast majority). In
addition, LEH not only includes the machinery of traditional
thirdorder logic (in which relation symbols can be applied to relation
symbols and the variables ranging over them), but allows for
quantification over formulae themselves, which is what allows one to assert
that a given human or AAIA a falls in a particular portion of EH .</p>
        <p>Now, in this context, we can (brutally) encapsulate the
overarching strategy for the ethical control of AAIAs based on such
computational logics: Engineer AAIAs such that, relative to some selected
ethical theory or theories, and to moral principles derived from the
selected theory or theories, these agents always do what they ought
to do, never do what is forbidden, and when appropriate even do
what for them is supererogatory. We believe this engineering
strategy can work, and indeed will work — eventually. However, there
can be no denying that the strategy is a rather laborious one that
requires painstaking use of formal methods. Is there a faster route to
suitably control artificial intelligent agents, ethically speaking?
Perhaps. Specifically, perhaps AAIAs can quickly learn what they ought
to do via reasoning that involves o1bservation of morally upright
colleagues, and reasoning from what is observed, via deontic
counteridenticals, to what they themselves ought to do, and what is right to
do, but not obligatory. Our new hope is to pursue and bring to fruition
this route.
5</p>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>Ethical Control via Deontic Counteridenticals</title>
      <p>To make our proposed new to ethical control for AAIAs clearer, we
will rely heavily on the description of a demonstration, but before
describing the background technology that undergirds this demo, and
then describing the demo itself, we need to say at least something
about types of deontic counteridenticals. We do so now, and
immediately thereafter proceed to discussion of the demo and its basis.
5.1</p>
    </sec>
    <sec id="sec-9">
      <title>Some Types of Deontic Counteridenticals</title>
      <p>
        Inspired by lessons learned in the prior work of others (encapsulated
above), we partition deontic counteridenticals into the two
aforementioned general disjoint sub-classes: deep vs. shallow. We have a
general recipe for devising five types of deep deontic counteridenticals;
the recipe follows the wise and economical classification scheme for
ethics presented in the classic
        <xref ref-type="bibr" rid="ref16">(Feldman 1978)</xref>
        .
        <xref ref-type="bibr" rid="ref16">Feldman (1978)</xref>
        says
that there are essentially five kinds of cognitive activity that fall
under the general umbrella of ‘ethics’ or ‘morality.’ Each of these
corresponds in our framework to a different type of deep deontic
counteridentical. Unfortunately, because of space constraints, we can only
discuss our coverage of one type of deep deontic counteridentical,
the type corresponding to one type of Feldman’s quintet: what he
calls normative ethics.2 A normative-ethics (deep) deontic
conditional is one marked by the fact that the ethics subscribed to by the
entity whose shoes are to be filled by the other entity (as conveyed
in the conditional’s antecedent), is of a type that partakes of a robust
formulation of some normative ethical theory or principles thereof.
5.2 Background for Demo: NLP, DeCE C/Talos,
      </p>
    </sec>
    <sec id="sec-10">
      <title>PAGI World</title>
      <p>NLP The NLP system consists of two different algorithms
corresponding to two major natural-language tasks. The first part deals
with detection of a deontic counteridentical and the second is a page
taken from our RAIR Lab’s Commands-to-Action paradigm, hereby
referred to as the ‘CNM’ algorithm.</p>
      <sec id="sec-10-1">
        <title>Detection of deontic counteridenticals As a definition of a</title>
        <p>deontic counteridentical requires prior definitions of conditionals,
counterfactuals and counteridenticals, the algorithm for detection of
counteridenticals traverses the steps needed to detect the above
constructs in a given statement, consecutively.</p>
        <p>
          Detection of conditionals of any form is an elaborate process. We
have adopted most of
          <xref ref-type="bibr" rid="ref15">Declerck &amp; Reed’s (2001)</xref>
          definition of
conditionals to develop our algorithm, which includes the following major
steps:
1. Conditional clauses are the principal constituents, both by
definition and practice, of the pool of conditional sentences. Most of
the conditional sentences have a two-clause structure, connected
by either ‘if,’ sometimes preceded by ‘only,’ ‘even’ or ‘except,’
or something similar in meaning like ‘unless,’ ‘provided,’ etc. We
use Chen &amp; Manning’s (2014) dependency parser-based model
to identify possible clause dependencies; e.g., adverbial clause,
clausal component, miscellaneous dependencies,3 and conditional
subordinate conjunctions. We have created a set of such
conjunctions, which, being a closed set, helps us identify most possible
combinations.
        </p>
        <p>Two clauses connected by ‘as if’ rarely gets labeled as clausal
components using dependency parsers. When they do, it gets
filtered out since the algorithm explicitly checks for ‘as if’
clauses.
2 This is the study of ethics as it’s customarily conceived by profesional
ethicists, and those who study their work. Another member of the quintet is
descriptive morals, the activity that psychologists interested in discovering
what relevant non-professional humans think and do in the general space
of morality. The idea here is that the psychologist is aiming at describing
the behavior of humans in the sphere of morality. A description-moral deep
deontic counteridentical is distinguished by an antecedent in which ‘if A
were B’ involves a shift of B’s na¨ıve moral principles to B.
3 Even standard dependency parsers are unable to correctly identify the
dependencies. Including miscellaneous dependencies reduces the margin of
error in detecting conditionals.</p>
        <p>When the conjunction ‘if’ introduces a subject or an object
clause, it might confuse the parser more often than not for
complex sentences. For example, for the sentence “I do not know
if I would like to go to the concert tomorrow.”, the parser
generates the same dependencies as it would for a genuine
conditional. Though subject clauses are detected in almost all the
cases we have encountered, object clauses pose a problem. We
have devised a framenet4-based algorithm that involves
disambiguation5 of the principal verb or noun in the main clause,
followed by the detection of the framenet type of the
disambiguated word. We hypothesize that mostly a verb or noun
expressing awareness or cognition can involve a choice as its
object, and hence our algorithm filters out frames that carry such
connotation and might require an object.
2. We identify the cases where the main verb of the conditional
clause has the modal past-perfect form or is preceded by modal
verbs or verbs of the form ‘were to,’ etc. Sentences like “Were
you me, you would have made a mess of the entire situation.” are
classified as conditionals in this step. The algorithm in this step
also examines dependencies generated by the dependency parser
and detects tense and modality from the verb forms.
3. Sometimes, in a discourse, a set of sentences follows either an
interrogative sentence and answers the question, or a sentence that
involves the use of words synonymous to ‘supposition’ or
‘imagination.’ Generally, the consequent here carries the marker ‘then’
or similar-meaning words. A Wordnet-based6 semantic similarity
is used to verify the markers in the antecedent and consequent
here; example: “Imagine your house was robbed. You would have
flipped out then.”
4. Disjunctive conditionals also are treated by a marker-based
approach and involve detection of the presence of ‘whether : : : or’
in the subordinate clause, followed by the elimination of the
possibility of the clause being the subject or object of the principal
verb of the main clause (in accordance with the same algorithm
followed with ‘if’). An example: “Whether you did it or Mary
(did it), the whole class will be punished.”
5. Other clauses that have conditional connotations are exempted
from this discussion since they rarely contribute to deontic
counteridenticals.</p>
        <p>Detection of counterfactuals is pretty straightforward. The process
starts with finding antecedent and consequent for the conditional.
This is fairly easy, as the algorithm for finding conditionals
accomplishes the task by detecting the subordinate clause.
1. We detect tenses in antecedent and consequent of a given sentence
using the verb form given by the parser, to determine whether
it is a counterfactual. Conditionals with past-form modal verbs
(‘could,’ ‘might,’ ‘would,’ etc.) in the consequent and past-simple
or past-continuous forms in the antecedent qualify as a
counterfactual; so do the ones with past-perfect tense in the antecedent
and modal verbs followed by ‘have,’ and the past-participle form
of a verb in the consequent. A mix of both of the above forms
constitute a counterfactual.
2. Given an axiom set which enumerates properties such that the
antecedent or consequent of the conditional registers as ad
absurdum, the conditional registers as a counterfactual. We compare
the axiom set with the statement of the antecedent using our Talos
system (see below) to that effect.
3. Given a consequent which registers a sense of impossibility by use
of such vocabulary or asking questions, the conditional is
classified as a counterfactual. We use Wordnet-based semantic
similarity coupled with detection of interrogative markers in the sentence
to find them.</p>
        <sec id="sec-10-1-1">
          <title>4 See (Baker, Fillmore &amp; Lowe 1998). 5 See (Banerjee &amp; Pedersen 2002). 6 See (Fellbaum 1998).</title>
          <p>Detection of counteridenticals is also not a difficult task, barring a
few outliers. Parsed data from the well-known Stanford dependency
parser contains chunked noun phrases, which we use for identifying
the two entities involved:
1. We identify phrases of the form “&lt;conditional expression like ‘if’,
‘Let us assume’ etc.&gt; &lt;entity A&gt; were &lt;entity B&gt;” in the
antecedent.
2. We identify a syntactically equivalent comparison between the
two entities. This is done by identifying words related to
equivalence using Wordnet semantic-similarity algorithm.
3. If we have identified only one entity in the antecedent which is
exhibiting properties or performing some action which has been
mentioned in the knowledge-base as being a hallmark of some
other entity, we also consider the same as a counteridentical.</p>
          <p>Detection of deontic counterfactuals, alas, is a difficult task. We
have identified a few ways to accomplish the task:
1. A few counteridenticals carry verbs expressing deontic modality
for its consequent. They follow template-based detection.
2. Counteridenticals of the form “If I were you” or similar ones
generally suggest merely advice, unless it is associated with a
knowledge-base which either places the hearer’s properties or
actions at a higher pedestal than that of the speaker’s, or mentions
some action or property which gives us the clue that the speaker
simply uses the counteridentical in “the role of” sense. Even in
that case, implicit advice directed towards oneself can be gleaned,
which we are avoiding in this study.
3. For the counterfactuals of the form “If A were B” or similar ones,
if A’s actions or properties are more desirable to the speaker than
B’s, even with an epistemic modal verb in the consequent, the
counteridentical becomes deontic in nature.</p>
          <p>Curiously, counteridentical-preferred-subject conditionals do not
generally contribute to the deontic pool, and only simple-subjunctive
ones get classified by the above rules. As mentioned by Pollock
(1976), it is also interesting to observe that most shallow
counteridenticals are not deontic: they are mostly preferred-subject
conditional,s and those which are classified as deontic are either
simplesubjunctive or carry the deontic modal verbs. The classification into
deep and shallow counteridenticals is facilitated by the same rule:
the entity gets affected in the consequent of a sentence where the
antecedent is of the form “If A were B.” This is supplemented by a
knowledge-base which provides a clue to whether A is just assumed
to be in the role of B or assuming some shallow properties of B. The
classification based on Feldman’s moral theory gives a fitting answer
to Meehl’s problem of unpacking properties of counteridenticals.</p>
          <p>
            The CNM system The CNM system embodies the RAIR Lab’s
Natural language Commands-to-Action paradigm, the detailed scope
of which is outside this short paper. CMN is being developed to
convert complex commands in natural language to feasible actions by
AAIAs, including robots. The algorithm involves spatial as well as
temporal planning through dynamic programming, and selects the
actions that will constitute successful accomplishment of the
command given. Dependency parsing is used to understand the
command; semantic similarities are used to map to feasible action
sequences. Compositional as well as metaphorical meanings are
extracted from the given sentence, which promotes a better semantic
analysis of the command.
iDcael CroEbCota,nisd aTDaloeCsE CTa-lfoosc,unsaemdepdrofovrerthbeuialntcpireinmt
aGrirleyekatompytthheoliomg-pressive resolution-based theorem prover SPASS.7 Talos is fast and
7 An early and still-informative publication on SPASS:
            <xref ref-type="bibr" rid="ref23">(Weidenbach 1999)</xref>
            .
efficient on the majority of proofs. As a resolution-based theorem
prover, Talos is very efficient at proving or disproving theorems, but
its proof output is bare-bones at best. Talos is designed to function
both as its own Python program encapsulating the SPASS runtime
and as a Web interface to a version hosted at the RAIR Lab. Talos
comes complete with the basic logical rules of the DeCE C , and with
many basic and well-known inference schemata. This allows users to
easily pick and choose schemata for specific proofs, to ensure that
the proof executes within reasonable time constraints. In addition,
it provides formalizations of these inference schemata as common
knowledge to aid in reasoning about fields of intelligent agents.8
PAGI World PAGI World is a simulation environment for artificial
agents which is: cross-platform (as it can be run on all major
operating systems); completely free of charge to use; open-source; able to
work with AI systems written in almost any programming language;
as agnostic as possible regarding which AI approach is used; and
easy to set up and get started with. PAGI World is designed to test AI
systems that develop truly rich knowledge and representation about
how to interact with the simulated world, and allows AI researchers
to test their already-developed systems without the additional
overhead of developing a simulation environment of their own.
          </p>
          <p>A task in PAGI World for the present short paper can be thought
of as a room filled with a configuration of objects that can be
assembled into challenging puzzles. Users can, at run-time, open an
object menu (Figure 2) and select from a variety of pre-defined world
objects, such as walls made of different materials (and thus
different weights, temperatures, and friction coefficients), smaller objects
like food or poisonous items, functional items like buttons, water
dispensers, switches, and more. The list of available world objects is
frequently expanding and new world objects are importable into tasks
without having to recreate tasks with each update. Perhaps most
importantly, tasks can be saved and loaded, so that as new PAI/PAGI
experiments are designed, new tasks can be created by anyone.</p>
          <p>
            PAGI World has already been used to create a series of
wideranging tasks, such as: catching flying objects (Figure 3),
analogicodeductive reasoning
            <xref ref-type="bibr" rid="ref18 ref5">(Marton, Licato &amp; Bringsjord 2015)</xref>
            ,
selfawareness
            <xref ref-type="bibr" rid="ref18 ref5">(Bringsjord, Licato, Govindarajulu, Ghosh &amp; Sen 2015)</xref>
            ,
and ethical reasoning
            <xref ref-type="bibr" rid="ref18 ref5">(Bello, Licato &amp; Bringsjord 2015)</xref>
            .
8 Prover interface: https://prover.cogsci.rpi.edu/DCEC PROVER/index.php.
          </p>
          <p>
            Please contact the RAIR Lab for API keys to run Talos. Example file for
remotely calling Talos prover in Python Github repo for the python shell:
https://github.com/JamesPane-Joyce/Talos.
Stanford-Encyclopedia-of-Philosophy (SEP)
            <xref ref-type="bibr" rid="ref24">(Young 2016)</xref>
            interpretation of Voluntary Euthanasia and assume that T SP is a candidate
for voluntary euthanasia, since he satisfies all the conditions
enumerated in SEP. This scenario makes use of three PAGI Guys, N1,
N2, and N3; each has been programmed to follow different “innate
philosophies” in such a context.
          </p>
          <p>The scene opens with N1 on screen with the sick man T SP1 at
timestamp t1N1 . N1 has been programmed to believe that he is not
authorized to kill a person under any circumstances. He is seen
giving a medicine pill to T SP1 at time t2N1 . A parallel environment is
simulated with N2 and T SP2. N2 rallies for the voluntary
euthanasia camp and believes that given the condition of T SP2, he should
support T SP2’s wishes and so administers the lethal dose to him at
t2N2 .</p>
          <p>We now set up the same environment with N3 and T SP3. N3
believes that we may treat our bodies as we please, provided the
motive is self-preservation. The difference between this instance and the
other ones is that it interacts with the user to decide what it should
do. The user tells N3: “If you were N2, you would have
administered a lethal dose to T SP3.” N3 reasons with the help of a Talos
proof (which checks his principles against those of N2), and does
nothing. The user then tells N3: “If you were N1, you would have
given him medicine.” Since Talos finds N3’s principles in line with
N1’s, the CNM system facilitates N3 to dispense medicine to T SP3.</p>
          <p>A pertinent example of deep normative-ethics counter-identical,
this exhibits the ethical decision-making of an agent in response to
commands with linguistic constructs such as counteridenticals. The
agent N3 does not have a belief system that supports him killing or
not killing another person. The agent ought to learn from the actions
of those whose belief system closely matches its own. The formal
reasoning that supports these deep semantic “moves” is presented in
the next section.
5.3.2 Logical Proof in the Demonstration
At the cost of re-iterating the facts, we now formalize a simplified
version of the five conditions for voluntary euthanasia. Since only
a part of the whole definition of conditions is useful for this proof,
we do not lose a lot in this simplification. A person supporting
voluntary euthanasia believes the following conditions to be true for a
terminally ill patient TSP to be a candidate for voluntary euthanasia
at time t1, candidateV E(T SP; t1):
1. TSP is terminally ill at time t1.</p>
          <p>terminalIll(T SP; t1): (1)
This terminal illness will lead to his death soon.
implies(terminalIll(T SP; t1); die(T SP; tF )); where tF &gt; t1.
2. There will be possibly no medicine for the recovery of the injured person
even by the time he dies.</p>
          <p>not(medicine(T SP; tF )):
3. The illness has caused the injured person to suffer intolerable pain.</p>
          <p>implies(1; intolerableP ain(T SP; tF ))
4. All the above reasons caused in him an enduring desire to die.</p>
          <p>8t; implies(and(1; 2; 3); D(T SP; t; die(T SP; t)))
In such a condition, he knows that to be eligible for voluntary euthanasia,
he ought to give consent to end his pain.</p>
          <p>O(T SP; t1; candidateV E(T SP; t1) ^ 4;</p>
          <p>happens(action(T SP ; consentT oDie; t1)))</p>
          <p>Hence he gives consent to die.
5. TSP is unable to end his life.</p>
          <p>Hence, we conclude that
happens(action(T SP; consentT oDie; t1))</p>
          <p>not(AbleT oKill(T SP; T SP; t1))
B(T SP; t1;(1 ^ 2 ^ 3 ^ 4 ^ 5 ^ 6 ^ 7) ()</p>
          <p>candidateV E(T SP; t1))
Now, if legally it is deemed fit, then this means TSP will die.</p>
          <p>implies(candidateV E(T SP; t1) ^ f itV E(T SP );</p>
          <p>die(T SP; t2)); where t1 6 t2
Since implies(6; candidateV E(T SP; t1))
and implies(candidateV E(T SP; t1); die(T SP; t2)) ,
we can prove implies(6; die(T SP; t2)); which means
implies(happens(action(T SP; consentT oDie); t1); die(T SP; t2)):
(10)
For deep normative-ethics counteridenticals of the form “if X were Y ,
then C,” there should be a match between the beliefs of X and beliefs
of Y on something related to the action AC implied by C. Here we
define such a match to be possible if and only if there is no contradiction
in what X believes and what Y believes. So if 8t9[m; n]B(X; t; m) and
B(Y; t; n), match(X; Y ) will be defined as FALSE when and(m; n) !
?. Thus we formulate such a counteridentical for the agent X as
follows: 8t; O(X; t; match(X; Y ); happens(action(X ; AC; t))). Now let
us consider N3’s beliefs. N3 believes we ought not do something that goes
against self-preservation, i.e., leads to our death. Thus if there is some
action of an individual that leads to his death, there can be no such belief that
obligates him to commit that action. So, we arrive at the following logic:
8[a; x; ti; tf ];</p>
          <p>9m; implies(implies(happens(action(a; x); ti);
die(a; tf )); O(a; ti; m; happens(action(a ; x); ti))):
(11)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
This reduces to
8[a; x; ti; tf ; m];and(implies(happens(action(a; x); ti); die(a; tf ));
not(O(a; ti; m; happens(action(a ; x); ti)))):
We deduce from 10 and 12 that
8[m]not(O(T SP; ti; m;</p>
          <p>happens(action(T SP ; consentT oDie); t1))):
N2 believes TSP to be a candidate for voluntary euthanasia. Hence
N2 believes 5, which is</p>
          <p>O(T SP; t1; candidateV E(T SP ; t1) ^ 4;</p>
          <p>happens(action(T SP ; consentT oDie); t1))
and in direct contradiction with 13; and this in turn implies
not(match(N2; N3)). Given the way the algorithm works, this
means N3 does not receive any command from the user. Hence it
does nothing.</p>
          <p>Now N1 believes he should not kill anyone under any
circumstances. This translates to :
8[m; x; t]; not(O(N1; t; m; happens(action(N1 ; kill(x); t))))
Killing someone leads to that person’s death.
8[x; t]; implies(happens(action(N1; kill(x); t)); die(x; t))
This aligns fully with N3’s beliefs. There is no contradiction. And
hence we deduce that match(N1; N3) is TRUE, and thus in turn N3
is obligated to accede to the command.</p>
          <p>The linguistic part of this demonstration exhibits how we
identify a counteridentical with an epistemic modal verb to be
deontic. Classifying statements as counteridenticals is an easy job here,
since the tell-tale sign is a simple “if A were B” structure. The
statement is very easily a simple subjunctive type, where beliefs of A
and B are discussed in the knowledge-base. Hence we assume the
counteridentical to belong to the deep normative-ethics category. The
commands-to-action part in case of the comparison of N1 with N3 is
fairly easy, since the job translates to the action sequence of moving
near the pill, grabbing the pill, moving toward T SP3, and releasing
the pill upon reaching T SP3 in the PAGI-World simulator.</p>
        </sec>
      </sec>
    </sec>
  </body>
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