1)
Why did he say "Lo Rabim Yechkamu"?
1.
Malbim: According to those who say that Chochmah is based on sense and experience, Chochmah is clarified via many researchers. Each relies on others' experiences, and they join to make Kelalim. I disagree. Special people have Ru'ach [of Chochmah].
2)
Do Zekenim understand Mishpat?
1.
Rashi: No - "Lo" applies also to this. Malbim - those who say that Chochmah is based on sense and experience, they hold that Zekenim understand, due to their many experiments and investigations. I disagree.


