I would probably lean towards Babe - but it is a tough one - balancing different eras, pre and post integration, etc. Would be interesting to see how some of the best players would have performed during a different time. Would Babe had a personal trainer and been more fit if playing in 2005, or would he have floundered against a more fit field (that had the best athletes of all races)? I suspect Ruth had so much talent, he would have adapted to any era, but would he have been as dominant? If Bonds played in 1915, he would be some footnoted entry as a great player in the Negro league and his over all greatness would be largely speculated (or Hank Aaron if he would have played a generation earlier than he did). With changes in physical conditioning and off season activities - would certain players have broken down sooner or held up longer if they played during a different time. Would certain hitting milestones or records not occurred due to improving defense etc.? I have no idea, but it makes me want to Netflex the Ken Burns baseball documentary sometime soon. It has been a few years since I have watched it.