Two Approaches to Commonsense Inferencing for 
Discourse Analysis. 
Marc Dymetman 
Universit6 Scientifique et Mtdicale de Grenoble 
Groupe d'Etudes pour la Traduction Automatique B.P. 68 
38042 Saint Martin d'H~res FRANCE 
Abstract: 
The dominant philosophy regarding the formalization of Commonsense 
Inferencing in the physical domain consists in the exploitation of the "tarskian" 
scheme axiomatization <-> interpretation borrowed from mathematical logic. 
The commonsense postulates constitute the axiomatization, and the real world 
provides the "model" for this axiomatization. 
The observation of the effective activity of linguistic communication and of the 
commonsense inferencing processes which are involved in it show the 
unacceptability of this scheme. 
An alternative is proposed, where the notion of "conceptual category" plays a 
principal role, and where the principle of logical adequation of an axiomatization 
to a model is replaced by a notion of "projection" of a conceptual structure onto 
the observed reality. 
1. Commonsense Inferencing in context: Commonsense and tile 
linguistic process. 
1.1 Disambiguation and Commonsense. 
Let's consider the following text fragment: 
"Mary ch~opped the plate on the table. It broke." fT. Winograd) 
It is quite clear that the disambiguation of the pronominal lexical reference of 
"if' (table or plate) involves, in addition to the syntactic and semantic constraints 
(where "semantics" is taken in a narrow sense of "formal semantics") a certain 
understanding of the natural structure of the described events. This understanding, 
shared by all members of the linguistic community, we can name it 
"Commonseuse". 
In the case at hand, commonsense informs us that: 
i) a plate dropped on a table will in all likelihood collide with the table. 
ii) when such a collision happens, it is not unlikely for the plate to break, 
but quite abnormal for the table to break. 
This shared Commonsense knowledge is taken into account at the pragmatical 
discourse level both by the speaker and the hearer, and allow the speaker to 
reconstruct, with the help of Gricean-type conventions of communication, 
the meaning intended by the speaker and therefore the correct pronominal 
reference: "it" refers to the plate. 
1.2 Linguistic Acceptability and Commonsense. 
The disambiguation problem just considered is closely linked to the problem of 
the linguistic acceptability of a text fragment. In the following example, the 
acceptability/unacceptability of the 2 texts is due to the possibility/impossibility 
on the part of the listener to reconstitute a direct causal link between the first 
element and the second element of each text: 
"John's parachute had teared to pieces. He crashed on the ground." 
*"John's parachute had got damped by the rain. He crashed on the ground." 
1.3 Reconstitution of the information implicit in discourse and commonsense. 
The previous examples showed already a relatively limited form of implicit 
information reconstitution in a piece of discourse: the text fragment was 
acceptable if it was possible for the listener to restore an implicit causal link in 
the text at hand. Here is now a more impressive example of implicit information 
reconstitution by the listener of a piece of discourse (fig. 1). 
Here, the reconstitntion of the informations implicitely contained in the original 
text makes use of at least 3 different domains of comreonsense: 
- commonsense in the physico/biological domain: to fall, to collide, 
disruptive consequences of collision, to be hurt, to die. 
- conmaonsense in the psychological domain: a murder consists in an 
intentional killing, i.e. with a plan the goal of which is the death of 
somebody. 
- commonsense in the social domain: the way in which society treats crime. 
"John was condemned to deat..h by th, e court. He had puslted 
his Wife out of the Window of t.heir 1Oth floor apartment" 
Implicit modellzatlon reconstructx, d by the listener: 
- dohm~ pushes his wife out of the lOth floor window 
- she fells fr~ thl 10th floor to the ~ound, ~athering speec 
all the ~lle 
- she collidas vlolentl~ with the ground 
- she i~ Seve~el~ httrt 
she dies 
on Inqulr~ I~ made 
- (he inqulr~ demonstrates the Intentlonallt V of doh~'$ act 
a coUrt ~eet5 o~d renders It~ verdict: doM is condemned to 
death for the et~der of his wife. 
Figure 1 
This example may serve to remind us of the easiness and the swiftness with 
which we are able to reconstruct a complex set of iaforntations implicit in a 
piece of discourse fi'om our mastery of Commonsense in a variety of domains 
simultaneously. However, iu the previously given examples, only the "physical" 
domain Cnatural phenomena") was made use of, and in the remainder of this 
paper, we will essentially restrict ourselves to this domain of Commonsense. 
2. The dominant model for Commonsense Inferencing in the 
physical domain. 
A considerable interest has arosen recently in A.I. for Commonsense 
modelizations of natural phenomena. The articles of Pat Hayes <Hayes 1978> 
seem to have set the tone for the philosophy presently predominant in the 
domain, of which the collections of papers <Hobbs, Moore (eds) 1985> and 
<Hobbs et at. 1985> can provide recent examples. 
The outlines of this attitude - which we call the Direct Interpretation approach 
(DI approach ) - towards Conuuonsense are the following: 
-The relation between theory and predictions is conceived ,as similar to what it is 
in "scientific" physics, but rite natural laws which are encoded in the theory 
are different: essentially they are of a nmre "qualitative" and less "namericar' 
kind. 
-The inferential procedure is made in tbe deductive mode (in the sense of 
"deductive logic", opposed to "inductive"). 
~Like "scientific" physics, "naive" physics should be able to predict - in a 
deductive manner - the greatest possible number of phenomena from the 
smallest possible number of general "natural laws", 
-"Naive" physics is a strictly objectivist physics: it describes reality "as it is": to 
be valuable, the laws and the consequences of the laws must be "true". 
-The description of the physical world is done through an axiomatization, 
typically in first-order logic, which respects the "tarskian" schema of 
semantical adequation of a logical theory to its model. In this schema, 
borrowed from mathematical logic (fig. 2.a), the real world is supposed to 
provide a model for the axiomadzation, which is a set of axioms representing 
physical laws which are verified in the model (fig. 2.b): 
0x 0y Polnt(x) APolnt(y) A x.y // 
"> 31z StralghtLine(z) 
A Inc(x,z) A Inc(y,z) 
\[~2 : model of Plene 
Geometry 
InAerpretttion Axlometlc theory of ............. , 
Plane Geometry 
Figure 2a 
obj 
On(ob~ surf) A Top(surf vol ) ~IF~ 
A 31iq Full(vol liq) 
flottable(obj )(-)Supports(vol obj ) 
(Pat Hages) 
Theory Hodel 
Figure 2b 
511 
3. Problems with the dominant model. 
3.1. Deduction or Induction? 
3.1.1. The linguistic examples given in section 1 demonstrate how difficult it is 
to consider the commonsense inferences which appear there as a process of 
purely deductive type. 
Thus, to take example 1.3, there is no logical necessity to the sequence of 
implicit events reconstructed by the listener: these informations are not 
deducible from the explicit informations "John was condemned by the court" 
and "John had pushed his wife out of the window": Maybe there was a safety net 
in place, and maybe John murdered a policeman 3 days later, and so on and so 
forth... 
Actually, the analysis of the type of inferencing which are involved in the 
reconstitution of implicit informations in the examples of section 1 is 
complicated by the fact that Commonsense is not alone in the picture here: 
pragmatical conventions of communication come also into play and exploit 
the elements of pure commonsense knowledge which are the ~ beliefs of 
the speaker and the hearer; place is lacking here for full discussion of this 
problem, but let's be satisfied with the following brief comments: 
At the level of discourse pragmatics, several types of intersentential 
"syntactical" relations between two contiguous declarative statements are 
possible: Cause, Parallel, Exemplification, Explanation .... 
<Hobbs 1984>. In the case at hand, it is the syntactical relation of 
Explanation which is realized between the first statement "John was 
condemned by the court" and the second statement "John had pushed his wife 
out of the window". 
This relation of Explanation can only be validated ~ Commonsense 
Inferencing is capable to provide a "natural" explicative chain between the 
first statement and the second statement. 
Finally, the speaker and the hearer share conventions (in the sense of Grice's 
"conventional implicature" <Levinson 1983> which allow them to "agree" 
about which of the admissible reconstructions is the intended one, perhaps 
with the help of a common evaluation of the degree of "naturalness" of the 
different admissible evenemcntial chains. 
At any rate, the commonsense inferencing level per se - which is exploited by 
the pragmatic level - seems difficult to reconcile with a purely deductive process. 
In fact, the type of commonsense inferencing used in the examples of 1.3 
presents certain striking similarities with the two following inductive/recognitive 
processes (by order of increasing complexity): 
If I observe a bike leaning behind a tree trunk hiding its central parts from me, 
1 will have no difficulty to induce the existence of a unique bike, and not of 2 
bike-halves placed in this exact position by a malevolent aesthete. 
In a movie, a sequence of two shots, the first one showing a woman writing a 
letter, the second one showing a man reading a letter will be interpreted as 
having a certain structural unity: it is the same letter, it has been sent by tbe 
woman and received by the man, etc... (Here again, as cinema is a 
communication medium, one must take into account not only the 
commonsense level, but also pragmatical conventions). 
3.1.2. Several attempts have been made recently to extend the standard deduction 
mechanisms of logic into "non-monotonic logics". These attempts have been 
relatively successfull in accounting for several types of "default reasoning", but I 
am not aware of any application of these techniques to the extended "gestalt-type" 
reasoning exemplified in 3.1.1. 
3.1.3. One of the other problems with the deductive approach of figure 2 is due to 
the difficulty there is to maintain the coherence of the thousands of axioms likely 
to be involved in any serious attempt to axiomatize any commonsense domain, at 
least if one supposes &s direct a relation of interpretation as the one in figure 2. 
The coherence of such an axiomatization is easy to guarantee in planar geometry - 
for instance -, thanks to the fact that the structure of the RxR model is 
mathematically limpid, and that the correctness of the axiomatization is assured by 
its adequation to its model. Quite other is the situation when we endeavour to use 
"reality" as our model, for we have no clear idea of the structure of this model 
prior to our attempt at an axiomatization. 
3.2. Commonsense observed. 
Another important difficulty with the approach of fig. 2 is due to its stricly 
"objectivist" character, i.e. its insistance that Commonsense formalizations should 
strictly respect the "reality" of natural phenomena. 
However, numerous psychological studies have unambiguously shown that our 
intuitive comprehension of physical phenomena differs considerably from the 
objective (scientific) physical state of affairs. Thus, the following experiment has 
been reported <Mc. Closkey 1983>: a sample of "naive" subjects were asked what 
they believed is the trajectory followed by a ball thrown horizontally. The results 
wem: 
5 % of the subjects believed that the ball travels first in a straight horizontal 
line, then falls straight down. 
35 % of the subjects believed that it travels first horizontally in a straight line, 
then curves down for a while, then falls straight down. 
30% of the subjects believed that it begins to curve down immediately but 
eventually falls straight down. 
(The scientific answer is that the ball follows a downward-oriented curve (close 
to a parabola) all the while). 
The many observations of this kind make it difficult, if not downright impossible, 
to establish a system of physics which is at the same time "naive" and 
"objective", unless one considers that naive physics does not necessarily have to 
copy the commonsense structure which is observed in human individuals. This 
attitude might be admissible - at least theoretically -, if one were attempting to 
give robots some understanding of the external world, but not if one seeks to 
modelize the processes which are at the root of linguistic communication, for 
these constantly make use of commonsense abilities actually present in Man. 
3.3. The diversity of phenomena accounted for by Commonsense. 
Perhaps the most important source of troubles with the deductive approach of 
section 2 has to do with the fact that, contrarily to "scientific physics", 
Commonsense is not free to delimit its experimental domain in an "ideal" way. It 
has to give an account, at its own level, of our cn:de experience of the world, as it 
presents itself "naturally", whether or not this experience conforms to universal 
physical laws. But this experience is extremely varied and undisciplined: for 
instance, although most physical bodies show a "natural tendency" to "fall" if 
unsupported, this is neither the case with spinning-tops, nor of moving bicycles, 
nor the case of mercury in an upside-down thermometer, nor clouds, nor planes, 
nor the case of the Moon, etc... 
It is difficult to imagine that there exist universal qualitative "naive" postulates 
from which one might deduce at the same time \]/.0.tit on one hand the unstability 
of a pencil set up on its point, and on the other hand the stability of a 
spinning-top or of a bicycle in movement. 
Also, many phenomena which Commonsense has no trouble giving an a 
posteriori account for are impossible to deduce from general laws, not only 
Commonsense laws, but often ~ laws too (in this instance, they are 
impossible or very difficult to deduce in practice, but more rarely in principle): for 
instance, the fact that a stone dropped into water will produce such-and-such a 
splash (a complex physico-mathematical fact); or, more dramatically, the fact that 
a cherry kernel planted into the ground will produce a cherry-tree, or even the fact 
that a moving bicycle is highly stable (even the experts do not seem to agree on 
the exact reason why it is so), etc... 
However, although all these phenomena are impossible to deduce from general 
physical laws, Commonsense succeeds in partially InRtJy.aliag them and 
them a posteriori with the help of general principles and schemata. 
(An enlightening discussion of the opposition between deduction and motivation 
in the domain of lexical semantics can be found in <Lakoff 1985>.) 
Let's give an illustration of what is to be understood by this a posteriori 
"structuration" of experience: our understanding of the behaviour of a 
spinning-top. 
512 
4. Structuration of Experience: the Spinning-Top, 
I~ and without claim to psychological accuracy (no experimental 
verification was made), Fig. 3 gives an idea of what an intuitive structuration of 
a spinning-top could look like: 
- Oo~ted obJ~ot, s~Jmn'~trtca) avouc~d an axll 
- set upright on it= po~ 
- hav~9 ~ fast rotattona| movement ~rotm~ Its =xts 
- tht axis oscillates around the yert~al d~rect~ 
- tht "rotmno~l lml~etul" fl =low~.y ~*ri~ll ~ut 
- t~o "~tlqe~tst teed/notes" are fl~tk~ 9 agak,~t each other : 
a) "natural t~nden¢V" of the object to fall dow~ 
b) t~nder~ 9 of the lxls to Ira U ©~se to the vertical dtre©t~on 
this last teMer~ V Is in I relMIon of meaotoat~-Iacreas~g ~etth Its 
Its "¢ausl" : the rotattonil rhovemea~ of the object ~rou~d its axis 
Figure 3 
Once structured in this manner, the spinning-top phenomenon is not any more a 
raw experience, but has become an informed experience: what we can call, 
following <Lakoff 1985> a "natural category". 
Several points should be noted: 
The structure of Fig.3 has only a remote connection to the actual mechanical 
structure of the phenomenon: there is no physical sense in speaking about a 
"tendency to stay vertical", and it is very problematical from the physics point 
of view to divide the phenomenon into causes and consequences. 
The spinning-top category has been structured with the help of a process of 
metaphorical importation <Lakoff, Johnson 1980> of pre-existing 
conceptual structures (which are categories too, but of a more abstract type, see 
section 5), most notably the structure of "two antagonist tendencies fighting 
against each other". This type of sUncture seems to be of wide use in language 
and thought and has been extensively studied by Len Talmy <Talmy 1985>. 
Another imported conceptual structure which has served to build the 
spinning-top category is the category of "natural impetus loss" which 
specializes here to a structure of "rotational impetus loss". (For a related 
notion, see the discussion of "Ohm's p-prim" in <DiSessa 1980>). 
TILe structure which has been given to tile spinning-top category is 
"explicative" (and "predictive") for a whole class of behavionrs of the 
spinning-top: thus, file fact that it is impossible for the top to stay vertical if 
it is not rotating, the top's stability loss with time (because of the loss of 
rotational impetus), etc... 
Tile structure of the spinning-top category is, in an essential way, 
nest-experimental: for an observer without experience of gyroscopic-type 
behaviour, the top should have "fallen" and it would not have constituted a 
priori a special category. From tile standpoint of such an observer, a cartoon 
showing a "spinning-top" losing its balance in the same way as a pen set on 
its point would have been perceived as the normal thing and would have 
constituted a dynamic category (see section 5) built with tile 
parallel-event construct (which is an abstract category) out of 2 
subcategories: "l~tll of an unbalanced body in contact with a surface" and 
"rotative movement of a symetrical body around its axis". What happens when 
the first actual spinning-tops experiments are observed is the fact that the 
observer becomes aware that this possible structuring of the experiments has 
to be rejected - it obviously does not fit the observed facts - and that a new 
"reading" of the experiments has to be built: a new category must be created, 
which ~ in a novel manner, on the one hand the rotational movement 
and on the other hand the natural tendency of the top to fall, by rendering these 
two factors causally dependent in the way given in fig. 3. 
5. An alternative to the Direct Interpretation Approach. 
In the remaining space, we would like to point out to another direction that 
research on Commonsense lnferencing could pursue. This will be done with the 
help of a "speech analysis metaphor". This metaphor should really be justified 
by a careful analysis of the inferencing processes that are at work in the modem 
generative approach to linguistics (as exemplified e.g. in <Kay 1979>), which 
space does not permit to be given here. Such an analysis would show that 
generative syntax - although it can indeed be reinterpreted in FOL, in about the 
same way as a high-level-language program can be reinterpreted in machine code 
- really relies on a quite different approach to interpretation than the tarskian 
theory/model approach. Namely, the same linguistic input can be interpreted by 
different competing ,511~~. Adding new predeflned structural 
descriptions to the linguistic theory (i.e. the grammar) will increase the range 
of the accepted linguistie-imputs, whereas adding axioms to a logical "theory of 
the world" decreases the range of accepted situation-inputs. 
5.1. A speech-analysis Metaphor for Commonsense Infemncing. 
The main features of the metaphor are illustrated in fig. 4: 
st,'uct~e "read" b~l the hm~lv" 
(.-.$~eech cleat n .-.') 
5\[ruct~Q ~rtod" b~ thin obleruet 
~('ituolion ir~ tht real ~orli~J 
words ~ ,i,ple conceptual eQXegori,s 
higher level ~truetures 0 0 higher level conceptual categories 
Figure 4 
In the metaphor, a parallel is made between: 
The unanalysed real world, wltich Commonsense "observes" and has to "make 
sense" of. I The unanalysed acoustical string, which the linguistic agent 
(here tile hearer) "observes" and has to "make sense" of. 
Tile FD (Functional Descriptions <Kay 1979>) of words are the elementary 
"blocks" out of which the linguistic structures are built / The simple 
conceptual categories (e.g. cat, dance ) are the elementary blocks out of 
which higher conceptual structures are builL 
The higher level FDs (e.g. those corresponding to VP) are used to build more 
complex linguistic structures. (There is really only a difference of level 
between this case and the preceding one.) / The higher level conceptual 
categories (e.g. the parallel-events category, the 
time-sequence-of-events category (see section 5.3)) are used to build 
more complex conceptual structures. (Same remark as before.) 
The linguistic structure "projecls " onto the sound-chain. There must be 
some "fit", bat it need not be perfect: the sound-chain may be nolsy and 
lacunary / The conceptual s~ructure "projects " onto the observed 
situation in the real world. There must be some "fit", but it need not be 
perfect: in fact the interpretative freedom is much more important here then in 
the speech-analysis case (see section 3.2). 
5.2 The different dimensions along which categories can be ordered. 
One can distinguish 4 axes along wich conceptual categories can be ordered 
informally: 
Along file complexity dimension, one can place, from simple to complex, 
categories representing: 
"simple objects": a chair, ,an apple 
"simple events": to eat 
"complex objects": a pair of shoes, a road network 
"complex events": a spinning top, a plane flying 
Along tile abstraction dimension, one can place, from concrete to abstract, 
categories representing: 
"concrete" categories: an apple, a cat 
more "abstract" categories: free fall of physical bodies, quantity-conserving 
pouring 
"abstract" categories: an oriented graph, causal sequencing of events 
513 
Along the productivity dimension, one can place, from fixed to productive, 
categories representing: 
fixed categories: John's bicycle 
more productive categories: an apple 
productive categories: causal sequencing of events 
The fourth axis, that of staticity/dynamicity is discussed in next section. 
5.3 How new categories are formed. 
The metaphor of section 5.1 between commonsense inferencing and the process of 
linguistic interpretation permits to transpose the generative approach of syntax to 
the plane of commonsense inferencing (fig. 5): 
tniUal blsi$ of st;bUt ¢~te~or%$ ~ eat'O°ri'$ 
a: 2-ant.agoni~ct-tendencles e: dPopplng 
b: naturol-i~petus-loss 9: ~Pir~lng-~oP c: tlme-s~quenclng-of-eu~nt$ L: john-takes-spinning-top-then-drops-it 
d: tok i ng-obj ec t- i n-hands 
Figure 5 
In this figure, there appear several types of categories: 
- i) The categories belonging to the "initial basis of static categories". 
They constitute the initial structural "stock" from which new categories are formed 
by the process of generation. In fig. 5 a, c, etc.., are the categories 
two-antagonist-tendencies, time-sequencing of events, which form the 
basis upon which higher categories are built. 
- ii) The categories belonging to the "extended basis of static categories". 
They are obtained through integration and coordination of several already existing 
static categories. An example that we have already seen is the example of the 
spinning-top category, which integrates (among others) the structures of 
two-antagonist-tendencies, natural-impetus-loss, and other structnres 
which we have not spoken of, as for instance that of abstract-containment. 
Static categories, contrarily to dynamic categories (see iii next), correspond to 
classes of reproducible phenomena, which, once structured into a conceptual 
category, become of general utility for commonsense processes and therefore need 
to be memorized permanently. For instance, once the spinning-top category 
has been formed to account for the experiences one has had of effectively observed 
spinning-tops, this category becomes of a general utility to: 
1) identify a spinning-top phenomenon as an instance of the spinning-top 
category. 
2) infer properties of this phenomenon thanks to the previous identification of 
the category. These properties are not directly perceivable in the phenomenon, 
but are described in the structure of the category which has just been identified. 
In the same way, to take a simpler example, once the static category of bicycle 
has been identified in a real situation, the perception of a fuzzy spot on the 
bicycle's front is sufficient to infer immediately the presence of a headlamp 
which is not directly perceivable (gestalt-type processing). 
Thus, the stock of already existing static categories serves to give structure to 
new categories of phenomena. We have seen in section 4. that these structures 
are, in many cases, necessarily post-experimental and cannot be O_¢.d.u.f,g~ a 
priori. 
The existence of categories pre-existing to the experiencing of new phenomena 
permits to the active observer to L¢C.0ggJ~ in the experience of a phenomenon 
the presence of simple or complex categories which are already known by him. 
514 
Thus, if the observed phenomenon had been different (for instance if the top 
behaved differently from what is the actual case), other pre-existing structures 
would have come into play: there would be in any case adaptation of the 
modelization to the observed experience. The difference with the philosophy of 
section 2 appears clearly here. 
- iii) The "dynamically produced categories". 
Dynamic categories (wbich we have also called "theorizations") differ mainly from 
static categories in that dynamic categories only "serve once" to structure an 
actually present concrete situation which is irreproducible (by definition, for it is 
"this" situation here and now). They are therefore created on the spot and are only 
temporary structures. For instance, the dynamic category t of fig. 5 corresponds to 
the concrete situation "John takes the spinning-top in his hand then drops it on 
the ground": The structuration of this category is partially shown on fig. 5: it is a 
category formed by integration of the categories spinning-top, 
taking-object-in-hands, dropping with (and "under") the productive 
category time-sequencing-of-events (we do not elaborate here on the 
question of what happens to a ~ top when it is taken in hands!). 
Space is lacking here for us to give a detailed discussion of dynamic categories and 
of the inferencing processes which manipulate them, 
which discussion must be postoned to a later study, but let us just give another 
illustration, related to the example of section 1.3: "John was condemned to 
death...". In this case, the speaker, who is supposed to have been the direct 
"observer" of the situation, has built a dynamic category which represents his 
understanding of the situation he has observed, and which is an integration of the 
dynamic categories "John pushes his wife out of the window", "she falls from the 
10th floor to the ground", etc.., themselves constituted from static categories: 
"pushing", "falling", "dying", etc... Furthermore, it is this dynamic category (or a 
part of it) that he tries to transmit to his listener through an efficient linguistic 
coding which is highly elliptical, and it is this dynamic category (or a part of it) 
that tire listener succeeds in reconstructing. 
The principal feature of the process of formation of new categories, whether static 
or dynamic, is that it is not basically a process of dg.O.afdJflll, but a process of 
of structures. This recognition is done. on the basis of a set of p.arlia!. 
informations about the phenomenon, which is what gives it its status of 
~. This is a crucial fact that cannot be detailed here. 
Let's only give one example: A sufficiently old child will ~ the abstract 
category quantity-conserving-interpouring in an ~ situation where 
Peter pours some wine from a bottle into a glass, although the invariance 
described by the category is not directly observable by her - indeed younger 
children, who do not yet possess this category, or a more abstract one over which 
this one is built, are not aware of this conservation, see <Piaget 1979>. 
Conclusion. 
We have tried to demonstrate the difficulties there are to apply a DI (direc t 
interpretation) approach to the formalization of our commonsense understanding oE 
the natural world. From a confrontation with linguistic phenomena and linguistic 
methodology, we have advocated a more indirect approach to interpretation. Work 
on a formal framework for this approach is currently under way. 
AKNOWLEDGMENTS: 
The author wishes to thank Len Talmy, Jerry Hobbs,Stan Rosenschein, Jane 
Robinson, Cbristian Boitet, Bob Moore and Pat Hayes for ideas, 
discussions and comments. 

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