Liquids play an important role in biological and engineered systems, facilitating adaptability and complex interactions with the environment. However, the specific role of liquid phase constituents in the emergence of embodied intelligence, especially in robotic systems, is not well understood. Previously, the role of liquids in embodied intelligence was considered primarily from a functional perspective without examining their classification within the system. Our comparative analysis of two systems—an actively controlled internal liquid rearrangement system and a passively controlled hygroscopic absorption system—demonstrates that bound liquids can be integral to an embodiment, while free liquids often serve as intermediaries or environmental elements. Thus, liquids could be classified as parts of the system, parts of the environment, and intermediaries, depending on the liquid state (bound or free), control mechanisms, and exchange with the environment. This understanding highlights liquids’ complex roles in intelligent behavior and emphasizes the importance of considering transient liquid-solid interactions at the system level. Recognizing the intermediary role of liquids enriches our understanding of embodied intelligence and may inform the design of more sophisticated approaches for robotic systems, bridging the gap between biological and synthetic systems.