http://www.snopes.com/politics/soapbox/cosby.asp
His naysayers are so full of shit (the last few paragraphs on the page).
Just look at the Asian minority in the US and all they state is clearly disproved and all he states is completely accurate.
They are now the majority in Ivy League schools and have a higher level of income than the majority of average and they do it with hard work and great parenting.
It is clearly and singularly cultural.
Just like those in the majority who are not parented properly and do not take advantage of their education.
Race is myth.