Death Note and Gundam SEED.
Death note really makes you think that with all the criminal on the loose what can you do to prevent them from hurting anyone else especially your loved ones. These people has no fear, they know if they got caught they'll only end up going to prison that provides free meals and a comfortable bed that the 3rd world country people don't even have.
Gundam SEED, well, have you seen The Island (American movie)? Its pretty much address the same question but with a different approach.

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There is no price in AWESOMENESS and ATTRACTIVENESS.

Provoking has three possible:
1. Speed Racer
2. Sailor Moon
3. Transformer

code geass!!!!

death note is thought provoking too, but it's too confusing so i don't feel like thinking about it

Code Geass and Gundam Seed

Eva 1st because it make you brain explode the first 2 times you watch it. Then spam series' like Bobobo because they are hiding a strong plot in the middle of the mess. Finally space anime from the 80's because they all tend to end in tragedy but people watch them anyway.

For me it's probably evangelion. It's like the only one I remember being provoking.

Death Note and Neon Genesis Evangelion. i mean like, W/ Death note the show like the length of the episodes are sooo short that ur not thinking bout the show, ur thinking bout stuff the show creates in ur mind during those 20 minutes

honey and clover.. it must be one of the best i ever saw.. makes you reflect on life

Serial Experiment Lain would be the most thought provoking anime I've ever seen before.

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