As good as Senna was, I don't think he was the greatest. I think it's simply impossible to label any single driver the greatest. You've no doubt heard various stories about Fangio's ability to read the road and car control but how would he have coped with the Turbo era or the current crop of cars with electronic driver aids. No-one knows.

Some drivers are better with very high powered cars, some are good when there is less grip, others excel where smoothness is required and so on.

I genuinely believe that if you had another driver with Senna's bloody-mindedness neither would have finsihed many races. He wouldn't have been called the greatest then. I think there is some merit in what Damon Hill recently wrote about Senna. I.e. he had to take some of the blame for the crash that killed him. Senna admitted deliberately crashing into Prost, negated his agreement with Prost not to race against team-mate, yet he was never called unsporting like MS has been.

Don't get me wrong, Senna was an excellent driver, but he was not god, he made mistakes, fewer than others, he was human.

I don't think any driver can be labeled greatest of all.