  Humans use signs, e.g., sentences in a spoken language, for communication and
thought. Hence, symbol systems like language are crucial for our communication
with other agents and adaptation to our real-world environment. The symbol
systems we use in our human society adaptively and dynamically change over
time. In the context of artificial intelligence (AI) and cognitive systems, the
symbol grounding problem has been regarded as one of the central problems
related to {\it symbols}. However, the symbol grounding problem was originally
posed to connect symbolic AI and sensorimotor information and did not consider
many interdisciplinary phenomena in human communication and dynamic symbol
systems in our society, which semiotics considered. In this paper, we focus on
the symbol emergence problem, addressing not only cognitive dynamics but also
the dynamics of symbol systems in society, rather than the symbol grounding
problem. We first introduce the notion of a symbol in semiotics from the
humanities, to leave the very narrow idea of symbols in symbolic AI.
Furthermore, over the years, it became more and more clear that symbol
emergence has to be regarded as a multifaceted problem. Therefore, secondly, we
review the history of the symbol emergence problem in different fields,
including both biological and artificial systems, showing their mutual
relations. We summarize the discussion and provide an integrative viewpoint and
comprehensive overview of symbol emergence in cognitive systems. Additionally,
we describe the challenges facing the creation of cognitive systems that can be
part of symbol emergence systems.
