Symbols as a Lingua Franca for Bridging Human-AI Chasm for Explainable
  and Advisable AI Systems
  Despite the surprising power of many modern AI systems that often learn their
own representations, there is significant discontent about their inscrutability
and the attendant problems in their ability to interact with humans. While
alternatives such as neuro-symbolic approaches have been proposed, there is a
lack of consensus on what they are about. There are often two independent
motivations (i) symbols as a lingua franca for human-AI interaction and (ii)
symbols as (system-produced) abstractions use in its internal reasoning. The
jury is still out on whether AI systems will need to use symbols in their
internal reasoning to achieve general intelligence capabilities. Whatever the
answer there is, the need for (human-understandable) symbols in human-AI
interaction seems quite compelling. Symbols, like emotions, may well not be
sine qua non for intelligence per se, but they will be crucial for AI systems
to interact with us humans--as we can neither turn off our emotions nor get by
without our symbols. In particular, in many human-designed domains, humans
would be interested in providing explicit (symbolic) knowledge and advice--and
expect machine explanations in kind. This alone requires AI systems to at least
do their I/O in symbolic terms. In this blue sky paper, we argue this point of
view, and discuss research directions that need to be pursued to allow for this
type of human-AI interaction.
