Update theory.tex

AAAI2021/tex/theory.tex

-\section{Experimental Setup}
+\section{ Symbolic Language Producing }
 \label{sec:thory}
 
-In this section, we introduce the experimental setup used in this paper,
-including the environment setup, agent architecture, and training algorithm.
+Before going to the detail of the training algorithms, we first introduce the environment, gaming rules, and agent architecture for enabling the emergence of symbolic language. 
 
 
 \begin{figure}[t]