So, finally the size of PHB's brain is revealed. It is so small that it can escape through his ears! Must admit though that it looks much bigger than a peanut.
@ Stui: I think Scott Adams assume we all know this is refering to MBA graduates who never had any work experience at all and are just fresh out of college/university. They're generally optimistic and had that "Know It All" aura. Oppose to those people with MBAs who had actually work experience and only went to do their MBA after 8-10 years of working. They know what's the working world like and are fairly more competent than MBA-newbies.