The way I see it, Reagan thought that intelligence was important, but it was not the most important thing. To Reagan, human freedom and truth were more important.
In a way, it takes a lot of intelligence to know the true value and limitations of intelligence. Reagan was able to achieve this higher level of intelligence.
Liberals, on the other hand, think that intelligence is all that matters. As a result, they're one notch below Reagan on the brain scale. It's the reason why Reagan was able to defeat them every step of the way.
Perhaps it is simpler than that. People of limited intellect have to make simple issues appear complex in order to feel smart. People of true intellect can pull simple truth out of complex situations.
Take for example Lincoln's address at Gettysburg. He captured everything that needed saying in a speech that takes maybe a minute or less.
Take for another example, George W. Bush's sparse but overwhelming words at the site of the WTC with that megaphone in his hands. "Can you hear me? [cheer] Well, I can hear you... and the people that brought these buildings down will hear from ALL of us soon!". In that one simple moment, the whole hideous 'compexity' of the moment was boiled down to simple truth that changed the focus of a nation. And hear from us, they did. In spades.
Simple, really. :-)