CENTENNIAL, Colo. (CBS4)– The Aurora theater shooting gunman’s notebook was entered into evidence in the theater shooting trial on Tuesday and released to the public on Wednesday. It provides new insight in the mind of James Holmes.

In a brown spiral notebook titled “Of Life,” Holmes scrawled a self-diagnosis of his “broken mind” and described his “obsession to kill” since childhood.

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Prosecutors have focused on portions of the notebook that detail Holmes’ planning of the attack and say it is evidence that he was sane at the time of the shooting.

James Holmes with this defense team in court (credit: CBS)

James Holmes with this defense team in court (credit: CBS)

Defense attorney Daniel King takes the opposite approach, saying confusing musings about Holmes’ life make up a greater part of the notebook. King cited ramblings by Holmes on the meaning of life and death, and the word “why” repeated over several pages.

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The notebook was received at the University of Colorado Anschutz Medical Center where Holmes had been studying in the neuroscience program until he withdrew. It was sent to Dr. Lynne Fenton, a psychiatrist he had been seeing. The notebook surfaced after the shooting.

A symbol found inside James Holmes' notebook (credit: CBS)

A symbol found inside James Holmes’ notebook (credit: CBS)

One page is titled, “The Questions” and below it, “What is the meaning of life? What is the meaning of death?” and at the bottom of the page a circle with the infinity sign and the number 1, the same symbol was found on Holmes’ calendar on July 20.

There are pages filled with the word “why?”

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(credit: CBS)

(credit: CBS)

There are also details of plans for the shooting, at the top the title is “Insights into the Mind of Madness” with stick figures drawn below and an equation that shows the value of murder is not equal to the dead.

Holmes has pleaded not guilty by reason of insanity for the July 20, 2012 shooting that left 12 people dead and dozens of others injured at the movie theater in Aurora.

In order to get a conviction the prosecution must prove Holmes was sane at the time of the shooting. The defense insists Holmes did not know right from wrong and indicated that even though his notebook shows he carefully weighed targets and methods, he could have been insane when the attack occurred.

Toni Billapando was with her friends when she tried to run out of the theater.

“I thought the rest of our group would be following us but that’s all I saw,” said said as she broke down on the witness stand in court Wednesday.

One member of her group, Alex Sullivan, was among those killed.

Another theatergoer at the movie that night was Stefan Moton. He testified that the incident left him a quadriplegic.

One of those who died in the shooting was Jonathan Blunk who was with his girlfriend, Jansen Young, when he was shot.

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“I sat up when the shooting stopped and then I tried to shake him and kept saying his name, Jon… Jon… Jon…” said Young.