<?xml version="1.0" standalone="yes"?>
<Paper uid="C02-2021">
  <Title>Reasoning in Metaphor Understanding: The ATT-Meta Approach and System</Title>
  <Section position="4" start_page="0" end_page="0" type="metho">
    <SectionTitle>
2 Mixed Metaphors
</SectionTitle>
    <Paragraph position="0"> Issues such as reasoning about uncertainty are particularly important in the processing of mixed metaphors. Mixed metaphors need not feature obvious cases of conflict but can include graceful combinations of metaphors, such as the following sentence to be examined below: One part of John hotly resented the verdict. This combines a view of John as made up of subagents and a view of agents' emotional states as things that can have temperature. It is possible to distinguish two types of mixed metaphor: parallel mixes and serial mixes. In a parallel mixed metaphor, the target (A) is seen partly through an A-as-B metaphor and partly through another metaphor, A-as-B'. B and B' are in general different domains, but may overlap.</Paragraph>
    <Paragraph position="1"> Also, different aspects of A may be involved in the two metaphors. In a serial mixed metaphor (commonly called a chained metaphor), the target (A) is seen as a source (B), which is in turn then seen as a different source (C).</Paragraph>
    <Paragraph position="2"> Previous work on the understanding of metaphor has assumed that mixing is a relatively rare phenomenon that can be handled once a more theory of simple metaphor is developed. We argue that this assumption is detrimental to progress since mixed metaphors rely on the same conceptual knowledge as simple metaphors and can, therefore, provide valuable insight into the processes and representations underlying metaphorical reasoning. Moreover, we claim that the reasoning processes and data structures involved in understanding mixed metaphors are identical to those used in understanding simple metaphors. Therefore, any current theory of metaphor should (at least in principle) be extensible to deal with mixing. To this end, ATT-Meta handles mixed metaphor in a manner consistent with the way it handles simple metaphors. The two types of metaphor are processed in subtly different ways. Parallel mixed metaphors create separate pretencecocoons that are mapped in parallel to the target domain where their respective contributions are understood. Serial mixed metaphors create nested pretence cocoons where the metaphorical view of B as C is nested within a pretence cocoon with the view of A as B.</Paragraph>
  </Section>
  <Section position="5" start_page="0" end_page="0" type="metho">
    <SectionTitle>
3 Reverse Transfers in Metaphor
</SectionTitle>
    <Paragraph position="0"> The use of metaphor involves a flow of effects of some kind from the source domain to the target domain, where effects can include insights into the target, hypotheses about the target, or the highlighting of parts of the target. However, although the overall effect flow is always from source to target, in many cases, this does not preclude a reverse flow where a literal proposition, command, or question is mapped onto an equivalent within the current metaphorical domain.</Paragraph>
    <Paragraph position="1"> The ATT-Meta system allows conversion rules to map from propositions in the source domain to propositions in the target domain and also in the opposite direction. So a source domain proposition such as &amp;quot;Socrates was the midwife for an idea&amp;quot; might be mapped onto the target domain proposition &amp;quot;Socrates helped in the production of the idea&amp;quot;. However, the rules would equally allow the proposition &amp;quot;Socrates helped in the production of the idea&amp;quot; to be mapped to the source domain proposition &amp;quot;Socrates was the midwife for an idea&amp;quot;. We argue that there are at least three reasons why ATT-Meta should have this ability: (1) Given that metaphors are ultimately used to have an effect on the target domain, the use of a metaphorical utterance can be seen as answering, in some sense, a target domain query. This sets up a choice between taking the metaphorical utterance and applying all conversion rules to it in the hope that one of the resulting propositions might provide a suitable answer, or taking the question and converting it into a question in terms of the current metaphor. We argue that the latter is often more efficient. (2) Certain source domain propositions would allow ATT-Meta to draw a tentative conclusion, which would, were it more strongly supported, provide an argument via a chain of reasoning for some other, target level, proposition or query. A target-level statement might give the added support, but for this to be the case it would first need to be converted into its source-level  equivalent.</Paragraph>
    <Paragraph position="2"> (3) The combination of source and target domain  information within a discourse that only intermittently maintains a metaphorical view of the target domain may best be done in the source domain after the target domain information has been &amp;quot;metaphorized&amp;quot;. This would be especially so if the source domain was information-rich compared to the target domain, so allowing much more reasoning to be carried out than would be possible in the target domain.</Paragraph>
  </Section>
  <Section position="6" start_page="0" end_page="0" type="metho">
    <SectionTitle>
4 Non-Declarative Metaphor
</SectionTitle>
    <Paragraph position="0"> Almost all examples of metaphorical language discussed in the literature are of declarative utterances rather than questions, commands, ejaculations, etc. However, these other forms of utterance can obviously occur. For instance, just as one can state &amp;quot;John is a steamroller'' one can ask &amp;quot;Is John a steamroller?'' Just as one can state &amp;quot;The champion knocked the cream-puff out'' one can issue the command &amp;quot;Knock that cream-puff out!'' The observation that questions, in particular, can be metaphorical, plays a significant role in our theoretical approach. This is because their processing is contiguous with that of implicit queries generated within the metaphorical pretence cocoon (see Introduction) during ATT-Meta's goal-directed reasoning.</Paragraph>
    <Paragraph position="1"> However, the theoretical significance of nondeclarative metaphorical utterances is even greater, because such utterances call into question accounts of metaphor that assume the task of understanding is to work out what claim about the target domain the metaphorical utterance is making.</Paragraph>
    <Paragraph position="2"> Compiling such examples is an additional goal of our corpus work (see section 6).</Paragraph>
  </Section>
  <Section position="7" start_page="0" end_page="0" type="metho">
    <SectionTitle>
5 Time and change
</SectionTitle>
    <Paragraph position="0"> Work is ongoing which addresses the temporal, aspectual and causal facets of metaphor. A survey of metaphors in the ATT-Meta Databank reveals, unsurprisingly, that the metaphorical expressions there involve a wide range of tense and aspectual constructions in English, including past, present and future tenses, simple and progressive aspects, and the full set of aspectual classes. A wide variety of temporal adverbials is also present. A key topic under investigation is the mapping of temporal and aspectual information between source and target domains.</Paragraph>
    <Paragraph position="1"> For example, if an event is telic in the source domain, to what extent does that telicity carry over to the target domain? Preliminary investigations confirm the expectation that such aspectual information is preserved in the majority of cases. Exceptions exist, however, and these merit further study.</Paragraph>
    <Paragraph position="2"> The mapping of temporal duration between domains is also being investigated. In some cases, a mapping appears to exist whereby an event of long duration relative to the source domain maps to an event with long duration relative to the target domain. This can be captured by an appropriate VNMA, which maps relative durations between domains. The logic of ATT-Meta is episode-based, which means that it is relatively straightforward to express this kind of constraint and employ it in reasoning.</Paragraph>
    <Paragraph position="3"> Currently underway is a detailed examination of metaphorical expressions involving both explicit and implicit temporal durations. This will result in a set of VNMAs covering a wide range of tense/aspect/temporal-adverbial constructions.</Paragraph>
    <Paragraph position="4"> A second strand of the work on time involves a detailed study of the metaphors used to describe times, states and events, including spatial metaphor for time (Lakoff 1994).</Paragraph>
  </Section>
  <Section position="8" start_page="0" end_page="0" type="metho">
    <SectionTitle>
6 Corpus Studies of Metaphor
</SectionTitle>
    <Paragraph position="0"> As an adjunct to the development of the ATT-Meta approach and system, we have been conducting corpus studies of metaphor, mainly using the British National Corpus but also using the Bank of English and, to a limited extent, web search engines. We have used both handannotation of small numbers of documents from the BNC and automated search for particular types of metaphorical phraseology (mainly relatively fixed metaphorical phrases concerning mental states) over the whole of corpora.</Paragraph>
    <Paragraph position="1"> Current objectives are (a) to develop large databanks of examples of various types of metaphorical utterance, for the benefit of metaphor researchers in general, (b) to demonstrate more extensively and objectively the importance in discourse of &amp;quot;map-transcending&amp;quot; metaphorical utterances (see Introduction), (c) relatedly, to reveal the degree to which relatively conventional metaphor phraseology can be varied in real discourse (cf.</Paragraph>
    <Paragraph position="2"> Moon 1998), and (d) to uncover (in small numbers of documents) the degree to which metaphorical utterances relate to context: how much their understanding depends on context and how much the understanding of the context depends in turn on them. We are interested in (d) because in the ATT-Meta approach the process of metaphorical understanding is partially guided by discourse goals set up by context.</Paragraph>
    <Paragraph position="3"> This feature goes a long way to side-stepping problems of apparent indeterminacy of meaning of metaphorical utterances when taken in isolation.</Paragraph>
    <Paragraph position="4"> We also have the methodological objectives of developing a good annotation regime for metaphor and better-automated search techniques for metaphor. As part of the latter, we plan to investigate the usefulness of a large set of morphological, lexical, syntactic and phraseological clues to the presence of metaphor, inspired by the clues discussed by Goatly (1997). These clues are only present in a minority of metaphorical utterances but could nevertheless form a useful weapon in the automated search armoury.</Paragraph>
    <Paragraph position="5"> Metaphor detection techniques developed for corpus study should also help with developing a means for an understanding system to notice the presence of metaphor. Such noticing is not currently performed by ATT-Meta but is an important topic for future research.</Paragraph>
    <Paragraph position="6"> Conclusion The ATT-Meta project is making headway in showing how metaphorical utterances can be computationally processed. It is based on a distinctive set of principles as to how to understand metaphor, some of which are original and some related to those of previous researchers. In particular, it seeks to avoid expensive computation of new analogical mappings between domains as a regular part of metaphorical understanding. This is inspired partly by the observation that genuinely novel pairings of domains are relatively rare in real discourse. What are more common are novel extensions of familiar metaphorical views, and novel mixes of views. This is true even in poetry (Lakoff and Turner 1989). The project is also seeking to take full account of the important role that uncertainty, gradedness and dynamism of situations plays in metaphor.</Paragraph>
    <Paragraph position="7"> The approach and system have been evaluated in a number of ways. We have applied the implemented system or the theoretical approach to (simplified versions of) selected real-discourse examples from an existing databank (http://www.cs.bham.ac.uk/~jab/ ATT-Meta/Databank): see Barnden (2001a), Barnden &amp; Lee (2001a) and Barnden &amp; Lee (2001b). We have applied the implemented system to examples of all the metaphors of mental states listed in the Master Metaphor List (Lakoff 1994, Lee &amp; Barnden 2001a). The examples here were found by search over the Bank of English. Finally, we have applied the theoretical approach to various real-discourse examples included in Goatly (1997): see Barnden (2001b).</Paragraph>
  </Section>
class="xml-element"></Paper>