A monster is someone who does terrible things with close to no remorse. In the novel Grendel by John Gardner, Grendel was misunderstood and often mistaken for a monster. In a study by Dr. Harry Harlow entitled "Attachment in Infant Monkeys", he determined that monkeys often associate behavioral issues with abandonment from their mothers. The question is, is Grendel truly a monster? Grendel is not a monster, due to the fact that he did all the killing and eating unknowingly.
Grendel cannot be held responsible for his actions. This is mainly because he has been rejected by his mother for years and in turn, it has taken a hefty toll on him. The countless murders he has committed do not even have a justifiable reason any more. For instance, the line "I let out a howl so unspeakable that the water at my feet turn sudden ice and even I myself am left uneasy" (Gardner pg.5) implies that not even Grendel is aware of the extent of his abilities. So when Grendel tried to interact with the humans, he didn't understand what to do, so the confusion caused him to lash out and became violent and delinquent. According to Dr. Harlow, children that do not get shown affection tend to grow up to have violent tendencies. .
With a lack of affection the baby's behavior would drastically change. For instance, in Dr. Harlow's study he concluded that "The behavior of these infants was quite different when the mother was absent from the room" (paragraph 8). This shows that without love and affection from their mothers the babies attitudes completely changed. In comparison to Grendel, Grendel has been raised his whole life with virtually no interaction from his mother. Keith Rice stated in his research on Dr. Harlow's experiment that "deprivation of emotional bonds to live mother monkeys (as infant monkeys) these (now adult) monkeys were unable to create a secure attachment with their own offspring" (paragraph 9).