It's quite obvious that they are both geniuses with amazing critical thinking skills. They both can analyse any situation from all angles in depth and come up with the best conclusion that would go over most people's heads. They're both excellent at the art of manipulation.
But who's smarter?
I think it is clear that L would beat Light in most intellectual / deductive / critical "games" if the latter did not have a Death Note. The primary advantage of Light was his Death Note, and that he was even able to convince two Shiringamis to write fake rules on it.
Furthermore, even with the Death Note, Light would have been beaten much earlier if he did not use Misa Misa or any other just as stupid man or woman who was willing to do the Shiringami eye deal, because he would never do it himself. So I am quite certain that L was smarter than Light, but Light prevailed due to his ruthlessness, his manipulative skills and, of course, his Death Note.
L was smarter, but Light was more manipulative because L was not a sociopath, unlike Light. L could be just as manipulative, he had the intellect for that, but his morals put some limit to that. That, the fact that Light had the Death Note, and L's popularity with stupid women such as Misa Misa was why Light defeated L.
Fanboy : a person who does not think while watching.share
Light is objectively smarter than L. His official stats put his Intelligence as 9/10. L's is only 8/10.
Check the Death Note wiki if you don't believe me.
You make good points but you can't disagree with the stats, Korios.
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