Your theme should take the form of an irresolvable dilemma, and so you should give both sides equal weight for as long as possible… until the climax. The trick is to come up a finale that addresses this conflict, and says something concrete about it, without definitively declaring one side to be right and the other side to be wrong.
Some would say the climax should simply re-state the thematic question in light of all that has occurred, but I would say no. I think in most cases it's important to tip slightly in the direction of one of the warring goods or bads at the end without dismissing either.
Let’s go back to data-mining our checklists. Each of the movies I looked at has an irreconcilable thematic dilemma, and nine of them tip toward one side in the end, but not definitively:
- Casablanca: The cause of freedom is ultimately more important that personal happiness…but it’s a tough call and a painful decision.
- Sunset Boulevard: Dignity is ultimately more important than success…but it’s a tough call and a fatal decision.
- In a Lonely Place: Self-preservation is ultimately more important than love…but it’s a tough call and a painful decision.
- The Shining: Self-preservation is ultimately more important than family loyalty…but it’s a tough call and a painful decision.
- Donnie Brasco: Family loyalties are ultimately more important than work loyalties…but it’s a tough call and a painful decision.
- Iron Man: Yes, societal responsibility is ultimately somewhat more important than individual achievement…but Tony still wants to be a bad-ass all the time, not a do-gooder.
- An Education: Yes, living up to one’s responsibilities is somewhat better than a life of excitement…but we sense that she doesn’t really regret her dalliance and she still longs to be more sophisticated than her parents.
- How to Train Your Dragon: Justice is ultimately more important than loyalty to family…but it’s an impossible choice so the two must be reconciled.
- Bridesmaids: Moving on is ultimately better than preserving old friendships…but it’s a tough call and a painful decision.
- In Alien, Ripley concludes that personal safety is entirely better than job loyalty.
- In Groundhog Day, Phil concludes that acceptance of one’s circumstances is pretty much entirely better than personal ambition.
- In The Bourne Identity, conscience is proven to be clearly better than duty. They could have attempted to make this more ambiguous by pointing to important missions that won’t get fulfilled due to Bourne’s crisis of conscience, but this is one case in which ambiguity would feel like the weaker choice: We see that the “vital CIA mission” Bourne was accomplishing was the execution of a deposed dictator and former CIA asset who was going to write a tell-all memoir. In this case, the need to show an irresolvable dilemma is trumped by the need to show the way the world works. We know that the CIA always claims that their dirty tricks are justified by their vital missions, and we also know that that always turns out to be bullshit. Indeed, the hapless reboot The Bourne Legacy does have a “but what about the vital missions?” scene, and it feels cheap and phony.
- At the end of Blue Velvet, Jeffrey has decided to restore his life to a level of naive idealistic artifice, but it is merely a mask for his yawning chasm of dark cynicism, and we sense that he’s still utterly torn between these two unpleasant choices.
- At the end of Silence of the Lambs Neither Clarice not the audience can decide whether it was worth it to work with one monster to stop another. It all depends on how much damage Lecter does.
- The conclusion of Sideways looks askance at both of our heroes’ philosophies (Jack’s boundless optimism vs. Miles’s clear-eyed cynicism), but refuses to privilege either one over the other. Ironically, each man achieves his own goal by reverting to type at the end and fails to influence the other one: Jack’s outrageous positive-thinking lies pays off for him, and Miles’s cynical honesty pays off for him.