[[WMG: Film/PayItForward's BrokenAesop is intentional.]]
It's actually a FamilyUnfriendlyAesop about the futility and limits of good deeds. Consider:

Every good deed Trevor does just ''barely'' escapes failure. The homeless man relapses into his drug habit; his mother's and Eugene's relationship turns sour not long after Trevor brings them together, and then fails ''again'' as her ex-husband comes back; and shortly after ''that'', the ex-husband becomes abusive again. Trevor only succeeds due to what appear to be very calculated plot points, and ''then'' with tons of angst on his part.

Also, why do [[spoiler:the bullies who murder Trevor, by all indication, got off scot-free? Not only that, but those people who allegedly "pay it forward" like Trevor ''for some reason'' don't do a bloody thing against them (possibly out of fright of being killed? apathy?). And what's worse, it's quite likely that many of Trevor's deeds are bound to be undone; for example, his mother might well become alcoholic again, due to grief from her son's death, which then turns their new relationship bad again, and so on.]]

Also also, the very premise of "pay it forward", as noted in the BrokenAesop entry, can mislead people into thinking that they only need to help people if someone has helped you, and after the quota of three people they don't need to help anyone else again. Who started this project? [[WideEyedIdealist Trevor, of course]]—and ''he's'' the only one who started helping people ''a priori''. A lot of people might have taken it up only for self-centered reasons, and didn't bother to continue the project because they had their own more important shit to do (which may explain why [[spoiler: they never bothered to bring the bullies to justice]])

All of this leads to some very unpalatable conclusions:
* Ordinary people are too afraid to take action when they see the slightest risk to their lives;
* [[HumansAreBastards People don't help other people for sincere reasons]];
* If you ''are'' sincere, your good deeds are bound to backfire and hurt you;
* Even if they ''do'' work, they probably won't last for long;
* All the good you do doesn't stop [[KarmaHoudini the bad guys from winning]];

Adding these all up: it's too much trouble to do good. Just keep to yourselves and you'll be fine.

As for the {{Glurge}}-y nature of the film, it might well be a StealthParody of similar {{Glurge}} stories, and possibly a stealth TakeThat towards idealists like Trevor—and by extension, many of the viewers.

* My God. I... I think I ''like'' the film now. '''[[BigNo Noooooooooooooooo!]]'''
* So the real lesson is, "be self-absorbed, because other people don't count?" I prefer idealism if the alternative is embracing outright ''selfishness'' as a "way of life". Not every situation will turn out identically, you just have to be careful about who you choose to help and think it through first.
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