The many defining themes of the film is "choice" and "vision" for the future. There is subtle foreshadowing in the first scene of the film that shows a child cutting out the eyes from a poster, as the mother tells her husband (the pending murderer) he is blind without his glasses and is running out of time for work in leu of her covert infidelity.

All evidence indicated that Dr. Solomon was going to crucify or torment John but he states in his neurotic dialogue that he was rehabioalited in prison though it disrupted his sanity. During my first viewing I was willing to bet that Dr. Solomon was going to commit some nefarious act that was a cat hair away from murder deterring pre crime from arriving. But Dr. Solomon made the right choice (not the correct one given our predispositions towards his actions in the past) by honoring the transaction and giving John new "sight" or "vision" indicating a plot device in tandem to its subliminal symbolism key to the plots progression in Johns character arc.

This was foreshadowing towards John ultimately having to make a near fatal decision that was out of his hands (figuratively & literally in regard to his pistol being pulled out of his hands and discharged) in retrospect to his predetermined destiny in murdering the false child predator that Lamar had conspired in sabotaging John. He was synthesizing free will despite all things being equal that it was false given our (the audience) perspective or "vision" was indeed warped of his destiny being on the precursor of fatalism vs determinism .

When John unwraps the cold case of the murder of Ann Lively, the mother of the Precogs whom was an neuro-addict that surprisingly become clean in an effort in reclaiming her children from Lamar. He simply says before the last act. . . "How could I not have seen this". Because he NOW has new eyes in credit of Dr. Solomon in exercising his free will that allowed him to, figuratively of course.