I was inspired

https://youtu.be/HU2ftCitvyQ

Lucid Dreaming and Anxiety - Frozen Journey

Have you ever gone to sleep after having a particularly emotional day? What about if you were expecting a particularly impactful tomorrow? Think about your dreams. Were they poignant and fixated on a single fear, exhilarant, or idea? If the dream became to much, you might try to wake up. But Imagine if it was a dream that for all intents and purposes could continue indefinitely. Wouldn't you prefer something a little more mundane?

It is understandable why the main character would choose to relive the same experience repeatedly for most of his trip, I'm sure that whole psychoanalysis thing was not comfortable. Most of us agree that at the end he actually does leave the ship, due to the fact that he we see his unusual actions from the perspective of his ex-wife, I think we were probably meant to think so.

For argument's sake let's say that the main character was still being fed the same manufactured "dream", even at the end. If the dream suddenly became more complex, diverse and suspiciously like reality from the main character's pov, should we assume he has woken up? Since this story showed how tricky and "mind bending" the concept of perception is, I think we could just as easily conclude that his mind had adapted to his state and fabricated a super convincing reality outside of the ship's control. I also want to bring the idea of lucid dreaming into this. Lucid dreaming seems to happen when a person is in a near meditative state. When a person, through practice, is able to let go of some of their anxieties or stressors during their dreams, they often report being able to change the dreams to their liking. Perhaps after years of the same "dream" he could become able to control it.

    I don't think Philip K. Dick was trying to make this point at the end, it was probably more along the lines of how the main characters mind was so conditioned to the "dreams". However, I just wanted to add something to the giant basket of things that makes the distinguished line between reality and false perception blurrier.

Hal's Motives

    

  Before I start writing about the subplot of Jupiter Mission, I'd like to state my position on the whole alien obelisk thing. I can't find any evidence in the movie to show that obelisks are for sure alien antennae devices or information messengers meant to advance humans; either way, it is pretty obvious that they are a) of mysterious alien origin and b) is highly involved in human advancement and discovery/ curiosity, whether that is in physical or metaphorical form. It also seems that the obelisk at least inspired or caused the evolution of modern day humans from the more animal-like prehistoric version. 
     Now to bring HAL into the equation, he is an AI that seems like the pinnacle of human advancement. Cerebrally speaking, he seems very similar to humans, in that he can reason, wonder, and feel. The few differences are that he can process even better than a human, but is still created to serve humans; although he eventually begins to question them. Because of this and the revelation at the end of his sentence, I have two theories behind Hal's odd lashing out towards the crew of Discovery One.
      Number 1: Hal seems to be far superior than humans as far as cognitive intelligence and likely figured out that aliens had something to do with thier motivation to explore farther into space from the top secret tape stored in his hard drive. While Hal may have been highly intelligence in other areas, he seemed to be immature as far as emotional or spiritual intelligence, which is possibly why he responded with fear and anger (both base emotions) at the unknown instead of the more human- like reactions of curiosity and risk taking. This is shown when Hal shows distrust towards the mission, a non-understanding of his emotions and reactions after trying to kill the crew members ("I am afraid, I am afraid"). This is the most distinct difference between humans and Hal, he does not show any interest in exploration; in his defense he had no choice but to venture into the unknown, which could understandably cause fear and frusturation (allthough, who's to say that man had any choice either) 
     Number 2: Similar to theory 1 in how Hal learns about the aliens. However in this theory, Hal's lashing out it caused by his vindictive personal interest. Perhaps, through Hal's superior database and intelligence, he figured that these alien obelisks had something to do with human advancment and feared that by venturing farther out humans would surpass machine once again in superiority. Maybe, Hal was so advanced that he experienced feelings of jealously and power hunger, and was planning all along to overthrow humans. (this theory is the most out there, but considering that Kubrick was probably on wicked acid, it's not as wierd as it could be)