Figure 21.1. Drawing of a chimpanzee that is “disappointed and sulky” after
an orange was offered to him and then taken away. From Darwin’s 1872 book
The Expression of the Emotions in Man and Animals.Whether or not nonhuman animals have mental experiences of
feelings associated with emotions remains a debated topic. Some
folks maintain language is necessary to produce a mental experience
of awareness, and absent substantial linguistic capacity there is only
an ability to respond in a nonaware, reactive way. However, perhaps
the more widely accepted hypothesis is that nonhuman animals
do have significant mental experience, including a capacity to feel
emotions such as pleasure and pain and to recall emotions they have
felt before and anticipate ones they may feel again. Human language
adds nuance and complexity to the texture of our mental experience,