Maybe Ran is to "pure" to naive in this sense. The Agasa-puzzle-things are canon, so if you go by anime originals a movies you'll end up with a different Ran again. Because unluckily the anime sort of forces Ran into the helpless girl-role, see the new trailer's "Save me, Shinichi" line.Girl19 wrote: There's a difference between being a freak and being a genius. Conan and Haibara might be too smart for their ages, yes, but Ran's intelligence isn't average for her age. I'm not saying she's stupid, but she's not smart either. And the fact that she, just sometimes, learns things quickly isn't enough to say that she's intelligent. You still see her, most of the time, being clueless about the easiest things such as Agasa-hakase's quizes. Even Sonoko is smart enough to figure them out, sometimes.
I'd also add that people often argue that Ran is not so bright, because she can't reveal Conan's true identity whereas she is the one who constantly brings up this matter although Conan and co. try their very best to prove that Conan is not Shinichi. Ran has a very flexible way of thinking, she basicly figured out 3-4 times in the manga, who Conan really was and if you look at her confession in Desperate Revival you can see that even Shinichi says: "She basicly/practically got/hit the point."
We know that people suspect that Conan is not an ordinary child, see Takagi, Sato etc., but none of them would actually think that he was shrunk by a drunk. And Ran did think of that, don't forget this.
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And (forgot to quote here sorry) yes, Shinichi first indeed wanted to keep his identity in secret, but again, in Deperate Revival he wanted to tell Ran anything, because that was the easiest and probably the best way. However Haibara opposed his idea and offered a third way, in order to protect her and Conan's identity and secret. Yeah, later on Shinichi again decided not to hurt Ran's feelings by telling her how he feels, and who he is, but at that point, Haibara was the one who created a new option for him.
About the protecting Ran part: since the BO kills off all the ones related to their targets, I don't think that they would observe or ask their relatives whether they knew about the secret or not. Remember that Vermouth almost killed Jodie, eventhough what can a child know about her father's secret work for the FBI?
Actually Shinichi's (mainly his) stupidity lies in the fact that he thinks keeping his identity in secret would save Ran if anything happen to him. That's nonsense. If Conan is ever captured, those who lived with him, including the already suspicious Kogoro and of course Ran will be killed. But maybe Conan is too confident in himelf. If Ran would know his secret maybe she could prepare for extreme situations, such as BO attacks or so. But if she doesn't know a thing, and doesn't know whom she could trust and so on, she would end up in dangerous situations. ike the Halloween Party case. That's why will her and Okiya's interactions will be interesting I guess.