Catherine’s emotions are as vivid and wild as her beauty. The theme of external looks and internal character is explored through Catherine’s emotional tantrums and the other characters who witness her tantrums. Catherine is intelligent, but she is also impetuous. Because Edgar loves Catherine, he has not seen her for her faults. He sees Catherine through rose colored spectacles, and he thinks she is perfect. It is not until their love is challenged by Catherine’s love for Heathcliff, that Edgar sees Catherine’s more volatile nature. Nelly, however, is not alarmed by the emotional tides of Catherine. She is used to the way that Catherine behaves, and the drama does not affect her in the same way that it affects Edgar.

When Catherine is young, she and Heathcliff would go playing on the moor at night. They would romp like kids. Catherine and Heathcliff were having an affair that no one would approve of. Catherine is like a tomboy at this point, she even spits like a boy. Catherine does not realize how to behave like a lady until something goes wrong on one of the times that she and Heathcliff go play on the moor. She is bit by a dog, and forced to limp up to the Linton’s Grange and recover there for five weeks. While she is there, Mrs. Linton take Catherine under her wing and provides instruction on manners and appearances. Her children, Isabella and Edgar, are immaculate in appearance. The way that the children look on the outside is how they behave on the inside.

One thing that Catherine does is to pretend to be a lady of high class and even disposition when she is first being courted by Edgar. She learned manners from his family, so she starts to lead a dual life. She is a lady around the Linton family, and she is wild around Heathcliff and the Earnshaw family. This causes Catherine to mislead Edgar into perceiving her as a complacent creature, when in fact she is anything but complacent. Edgar believes that Catherine is an intellectual creature, not an emotional creature. However, Nelly recognizes that Catherine is an emotionally shallow, non-intellectual person. When Catherine chooses Edgar over Heathcliff, she confides to Nelly that marrying Heathcliff would destroy her social status. Therefore, Nelly knows that Catherine is truly in love with Heathcliff, even though she chooses to marry Edgar. Edgar, of course does not know this fact, but he suspects it.

Nelly expects Catherine’s emotional reaction to Heathcliff’s return, whereas, Edgar does not. After Heathcliff has been gone for a long period of time, Catherine is breathlessly excited to discover that he has returned. She tries to share the news of Heathcliff’s arrival with Edgar, but of course, Edgar is not happy to hear the news. Unlike Heathcliff, who is Catherine’s doppelganger in many ways, Edgar is Catherine’s opposite. They are not soulmates. Catherine is unable to control her emotions and she confides in her husband: ’I know you didn’t like him,’ she answered, repressing a little the intensity of her delight. ‘Yet, for my sake, you must be friends now. Shall I tell him to come up?’” [italics] (Bronte 150). The fact that she modifies only a little of her delight is like water leaking through a dam; she is losing her ability to maintain her dual nature, and her true emotions are leaking through. And, she ignores Edgar’s feelings, insisting that he respect her feelings.

Nelly has a different perspective of Catherine, because she already knows that Catherine is living a lie when she married Edgar. Nelly does not attribute the same innocent and goodly intentions to Catherine that Edgar does. Therefore, Nelly sees Catherine Earnshaw, and Edgar sees Catherine Linton.