Beginning to analyze Mersault's motives for murder

What were Mersault's motives for this killing? "The sun" wasn't enough for the jury, and its not enough for me. Here is a passage that I think helps us understand:

"A minute later I turned back toward the beach and started walking.

    There was the same dazzling red glare. The sea gasped for air with each shallow, stifled little wave that broke on the sand. I was walking slowly toward the rocks and I could feel my forehead swelling under the sun. All that heat was pressing down on me and making it hard for me to go on. And every time I felt a blast of its hot breath strike my face, I gritted my teeth, clenched my fists in my trouser pockets, and strained every nerve in order to overcome the sun and the thick drunkenness it was spilling over me. With every blade of light that flashed off the sand, from a bleached shell or a piece of broken glass, my jaws tightened. I walked for a long time" (57).

This is right after Raymond and him encounter the two Arab men from earlier and decide not to shoot them. Mersault says he is "unable to face the effort it would take to climb the wooden staircase and face the women again" (56). He turns around and walks back along the beach, but clearly this is taking much more effort than simply walking up some stairs. What is driving him to press forward along the beach despite there being no shade in sight?

Soon, Mersault meets "Raymond's man", who is lying on the ground unthreateningly.

"It occurred to me that all I had to do was turn around and that would be the end of it. But the whole beach, throbbing in the sun, was pressing on my back. I took a few steps toward the spring. The Arab didn't move. Besides, he was still pretty far away. Maybe it was the shadows on his face, but it looked like he was laughing. I waited. The sun was starting to burn my cheeks, and I could feel drops of sweat gathering in my eyebrows. The sun was the same as it had been the day I'd buried Maman, and like then, my forehead especially was hurting me, all the veins in it throbbing under the skin. It was this burning, which I couldn't stand anymore, that made me move forward. I knew that it was stupid, that I wouldn't get the sun off me by stepping forward" (56, 57).

Mersault blames the sun for putting him in this trance that takes him from the stairs leading off the beach to the Arab man lying in the shade of the rock. He remarks that the sun was the same as it had been when he buried his mom, which seems significant. Let's take a look back to when he buried Maman.

"All around there was still the same glowing countryside flooded with sunlight. The glare from the sky was unbearable. At one point, we went over a section of the road that had just been repaved. The tar had burst open in the sun. Our feet sank into it, leaving its shiny pulp exposed... All of it, the sun, the smell of leather and horse dung from the hearse, the smell of varnish and incense, and my fatigue after a night without sleep-- was making it hard for me to see or think straight... Then there was the church and the villagers on the sidewalks, the red geraniums on the graves in the cemetery, Perez fainting (he crumpled like a rag doll), the blood-red earth spilling over Maman's casket, the white flesh of the roots mixed in with it, more people, voices, the village, waiting in front of a cafe, the incessant drone of the motor, and my joy when the bus entered the nest of lights that was Algiers and I knew I was going to go to bed and sleep for twelve hours" (16-18).

Mersault never expresses any direct grief for his mother, but he finds the funeral unbearable. He absorbs it all, and it drains him totally. He desires nothing more than to return to his home and forget about that unpleasant experience. And it appears he does, as the next morning he wakes up thinking about his boss. However, the sun on the beach reminds him of his mother's funeral. Is this just a physical observation, or a mental state? Mersault has said himself that his physical state often affects his mental state. So, the sun on the beach brings him back to his mother's burial, feeling the unbearable heat, the long walk, the desire to keep pushing forward until he is through the situation so he can move past it. He loses the ability to think rationally. We already know that the sun makes him tense up, his fists clench, and it takes effort to keep pushing onward. So when the Arab man raises his knife and the glint hits Mersault, stabbing at his eyes, while the sweat from his forehead clouds his eyes, its fair to say that he pulls the trigger as a knee-jerk reaction.

But what made him pull the trigger four more times?

I don't know, I've been writing long enough already. Do you know how long it took to copy those quotes down? Let me know what you think in the comments, and I might write about it in my essay.