Strange Change

Mersault undergoes an emotional change after the murder. Beforehand he lived his life solely by the physical implications, like for example if he ate it was only to get rid of his hunger. After the murder he becomes interested in the emotional and psychological perspective. The prison is the perfect setting for comparing the two because in a prison most pleasures aren't available, like cigarettes. The loss of the cigarettes is the first step, and it's apparent by even then he views it as an inconvenience because he's addicted to them.