The philosophy of language, which has historically been developed through an anthropocentric lens, is now being forced to move towards post-anthropocentrism due to the advent of large language models (LLMs) like ChatGPT (OpenAI), Claude (Anthropic), which are considered to possess linguistic abilities comparable to those of humans. Traditionally, LLMs have been explained through distributional semantics as their foundational semantics. However, recent research is exploring alternative foundational semantics beyond distributional semantics. This paper proposes Robert Brandom's inferentialist semantics as an suitable foundational semantics for LLMs, specifically focusing on the issue of linguistic representationalism within this post-anthropocentric trend. Here, we show that the anti-representationalism and logical expressivism of inferential semantics, as well as quasi-compositionality, are useful in interpreting the characteristics and behaviors of LLMs. Further, we propose a \emph{consensus theory of truths} for LLMs. This paper argues that the characteristics of LLMs challenge mainstream assumptions in philosophy of language, such as semantic externalism and compositionality. We believe the argument in this paper leads to a re-evaluation of anti\hyphen{}representationalist views of language, potentially leading to new developments in the philosophy of language.