don't even know why people are still debating this . of course mayweather is scared, he basically said it himself when talking about a pac fight in that vid at the end.
"i'm not scared... i'm smart, i care about my health, i don't care about the money, if i had to walk around with a limp or permanently scrunched over i would give all the money back"
that is a clear admission that he fears a fight with pac could permanently damage his health. he is scared of pac, end of.