The OTHER alien cities Brainiac shrunk

[ManSinha]

To play the devil's advocate to Mr. Super Monkey   , having a photographic memory does not in my opinion equate with super intelligence. If that were the case, Dustin Hoffamn in Rain Man would have also been portrayed as super intelligent!

The other facts though, I completely agree with.

[llozymandias]

luthor (untill 1986 anyway) did have super-intelligence.  in his first appearance luthor described himself as "just an ordinary man with th' brain of a super-genius".   being a super-genius would mean having super-intelligence.   superman was a super-genius.  super-memory was just one of his mental abilities.

[ManSinha]

luthor described himself

That is the pivotal term: described himself...me thinks the term "megalomaniac" would be better suited.

[NotSuper]

I've always theorized that Superman's so-called "super-intelligence" was just a combination of his ability to absorb information extremely fast and remember everything. I remember that he was described as having only above average intelligence in Last Son of Krypton. However, his ability to learn and deduce at much greater speeds and to remember everything greatly accelerated his intellect. You have to wonder just how intelligent the already brilliant Jor-El would be under a yellow sun.

As for Luthor, his pre-Crisis mind was so great you could almost consider it a super-power. But that may go against the nature of the character.

[ManSinha]

Genetics does play a role. At least in the Pre Crisis Universe, Kal-El was the pinnacle of evolution the best possible that Krypton had to offer. So if Jor-El was "brilliant",.....

[llozymandias]

according to "last son of krypton" (the novel)  kryptonian science had a way of meauring an individuals level of intelligence.  or if it's a child the intelligence they will develope as they grow.  jor-el used that to measure baby kal-el's intellect, & found that kal was smarter than him.  under a yellow sun jor-el would be kal's (at Least) near-equal in intellect.  kal without his powers would still be smarter than one einstein, instead of an army of them.  here is a kind of scary thought if luthor gained kal's powers what would  his resulting iq be?  keeping in mind lex is already super-intelligent & that gaining kal's powers basically amplifies all your abilities to an equal extant.  

   all megalomaniacs believe themselves superior to everyone else.  lex's megalomania comes from the fact that intellectually he is superior to pretty much everyone else.

[NotSuper]

You have to wonder if Luthor's intellect could be considered a super-power itself. Perhaps his mental abilities represent a new pinnacle of human evolution. Based on his great intellect, I would even theorize that Luthor already has total recall (or the human equivalent of it).

In terms of comparing intelligence, I would rank Brainiac above Luthor, and Luthor above Superman. The reason I rank Brainiac higher is because of the fact that he's a living computer, while Lex and Kal are carbon based life forms. In fact, I would wager that a being of Brainiac’s almost unlimited intellectual capacity would be smarter than most biological organism in the DC Universe.

[llozymandias]

i still place luthor above brainiac in intellect.  i alway saw brainiac as having very mixed feelings regarding lex.  a mixture of gratitude, admiration, curiosity, & fear.  gratitude, lex was the one who upgraded him from 10th level to 12th level.  admiration,  brainiac has admitted to being impressed by lex's intellect.  i don't see brainiac as being impressed by an inferior mind.  curiosity,  brainiac always believed that all humans were at best 6th level.  and here is lex who is clearly above 12th level.  fear,  in their first meeting (in addition to upgrading him) lex puts a bomb in his head.  lex did that to have leverage over brainiac.  in the process lex taught brainiac to never really trust him.  all in all, lex is the closest thing brainiac has to a friend.