If anything, Meursault is closer to being a psychopath than a sociopath. If you are to consider sociopathy and psychopathy different disorders (which many experts are no longer doing), then you would find a few subtle differences in the characteristics of those living with the disorders. Psychopaths tend to be more violent and impulsive, whereas sociopaths are much more calculating and likely to commit a premeditated crime. In addition, sociopaths tend to be able to maintain normal relationships, although their normality is often superficial. Thus, Meursault is much more likely to be considered a psychopath than a sociopath because his crime was very violent, impulsive, and not premeditated.
Even so, psychopathy is not a good diagnosis for Meursault. He would not score high on the Hare Psychopathy Checklist-Revised (PCL-R), the most common analysis of psychopathy. We simply do not have enough evidence to assess many of the traits on the list at this point in the book. So, I will quickly look at many of the ones that we can evaluate at this time.
- Glibness/superficial charm - You could consider his agreement (or lack thereof) and refusal to commit to anything a way of being 'superficially charming.' This trait could apply to Meursault.
- Lack of remorse or guilt - His excessive and unnecessary guilt has come up multiple times in the book and in class. This trait does not apply to Meursault.
- Shallow affect (genuine emotion is short-lived and egocentric) - His lack of emotion is not the same as shallow affect. This trait does not apply to him.
- Callousness, lack of empathy - He has displayed this multiple times, most notably when shooting the Arab. This trait could apply to Meursault.
- Need for stimulation/proneness to boredom - He sat and stared at the street he lives on for an entire day. This does not apply to him.
- Parasitic lifestyle - He is providing for himself, and was even providing for his Maman for a time. This does not apply to him.
- Poor behavioral control - Although he displayed this when killing the Arab, he seems to be very controlled for much of the time, especially when talking to people. He does not give his opinion, while not rejecting theirs. The jury is still out on this trait.
- Impulsiveness - He has displayed this a few times, most notably when killing the Arab. Often, when psychopaths kill people, it is because they don't like the attitude or look of a person or because the person is breaking some rule that the psychopath has established for themselves. This sounds sort of like a plausible reason for Meursault's killing of the Arab. This trait could apply to him.
- Irresponsibility - He provides for himself, and used to provide for his Maman. He kept Raymond from shooting the Arab. At the same time, he killed a guy. The jury is still out on this one.
- Promiscuous sexual behavior - Although he and Marie "hit it off" (so to speak) very quickly and many times, Meursault has stayed true to her. This trait does not apply to him.
Psychopaths are also fascinated by normal displays of emotion. The classic example is that if a psychopath saw a mother in the street grieving over her child who had just gotten run over by a car, they would a) be captivated by the child's mutilated body, b) not fully understand why the mother was making that face, what emotion it was, and how it was connected to the child's death, and c) go home and try to mimic her expressions. Psychopaths will try to learn from what they see around them to assimilate themselves with "normal" society. Thus, when you interact with a psychopath, it is very possible that their emotions will be dramatic, short-lived, and feel fake.
Although he ostensibly pointlessly murdered someone in cold blood, it is unlikely that Meursault could be considered a sociopath or a psychopath. He scores low on the HCL-R and displays many traits that go against the most basic aspects of psychopathy. Calling him a psychopath almost feels offensive to psychopaths. However, I think that this makes him something worse than a psychopath - something scarier. His complete lack of emotion and near inability to relate to people almost makes him inhuman.