The Era of Semantic Decoding
Maxime Peyrard Martin Josifoski Robert West
Recent work demonstrated great promise in the idea of orchestrating
collaborations between LLMs, human input, and various tools to address the
inherent limitations of LLMs. We propose a novel perspective called semantic
decoding, which frames these collaborative processes as optimization procedures
in semantic space. Specifically, we conceptualize LLMs as semantic processors
that manipulate meaningful pieces of information that we call semantic tokens
(known thoughts). LLMs are among a large pool of other semantic processors,
including humans and tools, such as search engines or code executors.
Collectively, semantic processors engage in dynamic exchanges of semantic
tokens to progressively construct high-utility outputs. We refer to these
orchestrated interactions among semantic processors, optimizing and searching
in semantic space, as semantic decoding algorithms. This concept draws a direct
parallel to the well-studied problem of syntactic decoding, which involves
crafting algorithms to best exploit auto-regressive language models for
extracting high-utility sequences of syntactic tokens. By focusing on the
semantic level and disregarding syntactic details, we gain a fresh perspective
on the engineering of AI systems, enabling us to imagine systems with much
greater complexity and capabilities. In this position paper, we formalize the
transition from syntactic to semantic tokens as well as the analogy between
syntactic and semantic decoding. Subsequently, we explore the possibilities of
optimizing within the space of semantic tokens via semantic decoding
algorithms. We conclude with a list of research opportunities and questions
arising from this fresh perspective. The semantic decoding perspective offers a
powerful abstraction for search and optimization directly in the space of
meaningful concepts, with semantic tokens as the fundamental units of a new
type of computation.