Tuesday, April 18, 2023, 2:00 pm – 6:00 pm
You are cordially invited to the Defense of PhD thesis
titled
THE PEDAGOGICAL ORIGIN OF HUMAN COMMUNICATION
by
Nima Mussavifard
Primary supervisor: Gergely Csibra
Secondary supervisor: Dan Sperber
Thesis submitted to:
Central European University, Department of Cognitive Science
ABSTRACT:
Human ostensive communication is believed to be a distinctive cognitive and behavioral trait. This thesis investigates the origin of this communicative system from an evolutionary and developmental perspective. Since addressing this question requires a specified explanandum, chapter 2 explores various accounts of ostension. I suggest that the difficulty of characterizing ostension may originate in evoking mostly mechanistic notions. For instance, higher-order intentionality focuses on the internal processes underlying communication and obscures their function. Likewise, attention manipulation draws on attentional mechanisms and fails to account for cases that go beyond highlighting perceptual phenomena. I propose, instead, to define ostension as involving nonnatural marking, i.e., the act of marking actions as communicative. This function can be implemented in various mechanisms and enables generating communicative means open-endedly.
Chapter 3 discusses the diverse selective scenarios proposed for the evolution of human communication. These scenarios are assessed against five criteria suggested by scholars for sound evolutionary accounts: uniqueness, immediate utility, generality, honesty, and cooperativeness. I show that scenarios stressing non-verbal modalities and the transfer of semantic contents are more successful in satisfying immediate utility and generality. Overall, most theories do not offer convincing explanations for the uniqueness of ostensive communication.
In chapter 4, I present my proposal for the origin of ostensive communication: it evolved to enable teaching technological knowledge. Hominin technology involved opaque skills that demanded demonstration and ostensive marking. Unlike other scenarios, demonstrating technological knowledge uniquely requires open-ended communication. Demonstrations are of immediate utility due to using objects and actions, rather than conventions. Demonstrations also satisfy the generality criterion, because they flexibly exploit stimuli to represent displaced generic contents. Finally, inclusive fitness explains why honest, cooperative communication was possible in early interactions.
If ostensive communication evolved in demonstrations, these may already contain some of the properties of language. In chapter 5, I argue that demonstrations possess a predicate-argument structure. Previous work has suggested that objects in
demonstrations may act as exemplars symbolizing their kind. I propose that actions on these object-symbols work like predicates in revealing hidden properties. The effect of actions on objects and their relations can be interpreted by infants as predicates ascribable to the kinds.
Chapter 6 investigates what a concept of communication involves. The standard answer is that communication requires complex metarepresentations of mental states. This complexity is at odds with the limited abilities of infants. But mentalistic metarepresentations are neither necessary nor sufficient in explaining communication. Ostensive signals rest on decoding rather than metarepresentational inferences—thus, some metarepresentations may be unnecessary. However, mentalizing is also insufficient for explaining communication: the logic of instrumental actions permits interpreting their effect as following from intentions. However, communicative effects are often unavailable for inferring meaning. My proposal is that the primitive concept of communication targets, instead, representational action. When we communicate, we typically convey a content that is detached from our acts. This representational property is absent in ordinary goal-directed actions. This account additionally raises the possibility that metarepresentation emerged for representing external, communicative representations and was later exapted for other purposes.