Asking some deep questions:

The story follows Section 9, a public security agency headed by Motoko Kusanagi, tasked with finding an elusive uber-hacker known only as the Puppet Master. This mysterious criminal is able to hack into the bodies of others, effectively rendering them simply as shells (hence the title) in order to alter the memories and conscious state of their minds.

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Given the major current interest in the science of ageing and "internet of things", this film couldn't be more relevant. In fact, Kusanagi has an interesting monologue early in the film, where she discusses how her world was only dreamt of as science fiction not so long ago, where a body's metabolism and biological processes still matter, but they can be separated from someone's thoughts and memories. We should remember that the film takes place in 2029.

Kusanagi also questions what her existence means or even is, and whether she is just a synthetic being created by scientists, with neurological implants aimed at making her more productive. She asks her colleague Batou, "I mean who knows what's inside our heads. Have you ever seen your own brain?" and examines whether a hyper-connected cyborg could create its own soul all by itself? This scene ultimately poses the final scary question: what is the purpose of being human?

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For many, many years, philosophers and super-smart thinkers have asked the question what it actually means to be human, both literally and figuratively. Philosophers have been thinking about the “zombie” scenario: there could theoretically be two identical versions of a person, able to carry out actions in exactly the same way, but one might not show any signs of consciousness. The doppelgangers are just replicas. This film asks what it means to be conscious and whether an identity of ours exists outside the immediate physical realm.

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What role will humans play in a future world where more tasks will be sufficiently carried out by robots?

This topic is mentioned in the film, as the Puppet Master quips bluntly about the dangers of depending on technology too much, and the threat of a virus being able to corrupt a whole set of interconnected systems. They go on to say copies aren't much use either, as they "do not give rise to variety and originality. Life perpetuates itself through diversity".

Perhaps Ghost is hiding a simple morality tale, warning us of the need to be more original. But we can only do that if we know what our unique identities are and the purpose of our existence. We'd better hurry up though. As the Puppet Master says, “the net is vast and infinite”, and we can’t lose ourselves inside a meaningless abyss.

1400+ Reddit comments:

https://reddit.com/r/Futurology/comments/48iioy/ghost_in_the_shell_over_two_decades_old_remains/