In Hitchhiker’s Guide to the Galaxy, Marvin refers to himself as a
“manically depressed robot”.
Manic depression (bipolar disorder) refers to someone who experiences
large emotional swings: ecstatic one moment and depressed the
Marvin never experiences ecstacy. His behavior more closely resembles
Marvin also displays no signs of paranoia, although he never claims to
be paranoid: the name “paranoid android” was probably given to him by
the not-always-bright Zaphod Beeblebrox.