Greatest Chess Master in History

I do.  But nobody has nominated him yet.

Igor Ivanov was a great Russian emigre who beat Karpov even though he was only an IM at the time. He won several US Grand Prix tours by traveling all over America playing in any weekend tournament he could find. He also was a heavy drinker who lost to class B players almost as often as he beat elite players.  He eventually earned his GM title. I had the great fortune to play a couple of casual blitz games against him in the 1980s. I drew as Black in a Spanish Exchange, but then got blown off the board as White against his Nimzo-Indian. 

Forkedupagain nominated him on the second page of this thread. According to Fork, "Well he did beat karpov in a tournament once. He also showed up to a tournament I'm not sure what year, drunk and lost to a 1300 level player. He was rated at 2500 at the time that's the largest margin of victory' that I've been able to find for a low rated player. He was concert also a concert pianist and a pretty remarkable guy... But he my have had a little drinking problem."

Tongue-in-cheek nominations are accepted. Well, within reason. I rejected nominations of "grandma" and "grandpa."

Hey, you drew the guy who beat Karpov.  Not bad.  But was he sober at the time?  

my list would be Fischer, Kasparov, Alekhine, Lasker, Capablanca in that order.

I don't think so. Every time I saw him, he was either playing chess or drinking. Sometimes, both at the same time. Still, he was good enough to win most tournaments he played in. 

I once played Bobby Fischer back in my prime when I was rated around 2500, and I managed to secure the dub. Fischer wasn't that great, so I think Vishy is a much better player.

All good choices.  That's another vote for Fischer.

What year did he beat Carlsen and what year did you beat him?

Yeah, back in your prime.  Uh huh.

My Karpov number is two: I beat Larry Christiansen in a simul, who beat Karpov. I won an autographed book for my effort!

He would've had a better career if he didn't play drunk but he probably wouldn't have enjoyed it as much.

Very good!

he beat carlsen when they were teens and i beat him 3 years ago! massive result!

ok, he did blitz while i took my time and it wasn't a simul, he only has himself to blame for getting outplayed.

he is a member here, a titled guy from norway, i forget the name. sigmundsen or something like that.

I shall do that. Mikhail Tal is the greatest chess master of all time!

next 4: Karpov, Fischer, Capablanka, Petrosian

Carlsen is not in list yet

Okay, that counts.  Carlsen was pretty good when he was a teen.