According to a conventional view, the most fundamental difference between humans and the other great apes is humans’ more highly developed capacities for thought and language – in other words, our superior intellects. A more decisive difference is the human capacity for feeling, and it is this that has enabled us to develop our cultures. As Damasio points out, however, cultural behaviours do not exist only in ‘minded creatures’. They can be found in very simple unicellular organisms, which rely on chemical molecules ‘to detect certain conditions in their environments, including the presence of others, and to guide the actions … needed to organize and maintain their lives in a social environment. For instance, bacteria can sense the numbers in the groups they form and in an unthinking way assess group strength, and they can, depending on the strength of the group, engage or not in a battle for the defence of their territory.’ Organisms without minds display kinds of behaviour we normally reserve for animals like ourselves; though humans do not descend directly from bacteria, our lives are governed by the same imperatives. The common thread linking the two is a process of homeostasis, operating in organisms to secure not only their survival but also a state of flourishing. This is where feeling comes in: ‘Feelings are the subjective experiences of the state of life – that is, of homeostasis – in all creatures endowed with a mind and a conscious point of view.’
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