One of the great inefficiencies of history is that most of it happens before we're paying close attention.
Someday, somebody will hit 763 home runs in a career and pass Barry Bonds. We will definitely pay attention to that home run, and to at least the few dozen or so that precede it, knowing that each one is 1/763rd of an unprecedented achievement. But most of those 763 will occur in the dull everyday. You will not be able to recall them, let alone describe them in full color for your grandchildren. That's the price we pay for being realistic.
Cody Bellinger set some records this week, I guess. He is the only rookie to hit 10 homers in 10 games. He has more multihomer games in his first 52 games than anybody else. He is the fastest ever to hit 22 home runs in a career. He's now in the Big Book Of Records, right after the guy who has hit the most multihomer games in his first 51 games (whomever that is) and right before the guy who is the fastest ever to hit 23 home runs in a career (whomever that is).
These are cute. I'm ready to think bigger. I'm ready to invest in something unrealistic and watch Cody Bellinger with one thing in mind: He might be hitting 763 home runs, right now in the present tense, and I plan to enjoy the significance of every single one of them.
Or he's not. Let's consider the ways of thinking about it.
Obviously, he will not: There Is 0 percent likelihood Cody Bellinger will hit 763 home runs.
Nobody has ever hit 763 home runs, so it's probably impossible.
Now, many things that have never been done are physically possible and eventually get done. Nobody had ever invented a polio vaccine, and then somebody did. Nobody had ever hit 762 home runs, and then somebody did. There are trillions of examples of things that have never been done and never will be done. The vast majority of things that have never been done, then, will never be done, and the most likely conclusion is that something that hasn't been done won't ever be done.
Hitting 763 home runs is probably impossible, and if Bellinger tries, his lungs will collapse and his head will explode.
Wally Berger existed: .1 percent likelihood
The guy who had previously been the fastest to 22 home runs was Wally Berger. I bet if you offered Berger's career to Bellinger right now, "Let's Make a Deal" style, he'd, a) have never heard of Berger, and b), accept your offer upon reviewing Berger's career. Berger spent most of the 1930s as one of the game's best players. He received MVP votes five years in a row, led the league in homers and RBIs one year and was sort of historically relevant for almost 80 years, until Bellinger came around and took his record -- or whatever we're calling it. If Bellinger had Berger's career right now, he'd probably make more than $200 million before retirement.
Berger did not hit 763 home runs. He hit 242 home runs. The gap between a good Bellinger outcome and the career home run record is the difference between how many times you've heard Berger's name and how many times you've heard Hank Aaron's.
We did actual math: 0.3 percent likelihood
Dan Szymborski ran ZiPS projections for Bellinger's next forever, and the results are awfully fun. For instance, Bellinger has more projected future value (by WAR) than any other existent first baseman or left fielder. He just passed Anthony Rizzo.
Two months ago, ZiPS projected Bellinger to produce 33 career WAR, but it has since flipped for him -- just like the rest of us -- and now projects him for 42 more career WAR. That means that, at 21 years old, with every imaginable landmine between him and retirement, Bellinger's average career is already as good as Don Mattingly's or Darryl Strawberry's. (Speaking of every imaginable landmine.) Berger's WAR, incidentally, was 41.9.
But we don't care about WAR. We care about dingers, and these are the chances that ZiPS puts on him reaching certain career home run milestones:
400 HR: 73 percent likely
500 HR: 54 percent
Let's pause here: If we believe ZiPS -- an educated weighting of Bellinger's statistical performance thus far, layered atop the demonstrated trajectories of historical baseball careers -- Bellinger is most likely going to join a club that has only 27 members. He is most likely one of the 28 greatest home run hitters who has ever lived. If you are buying any of this, you're excited. If you're not buying it, it's fun for me to imagine the look on your face as you stare at me with pity and disgust.
600 HR: 21 percent
700 HR: 2.2 percent
756 HR: 0.5 percent
763 HR: 0.3 percent
So that's the math number: 0.3 percent. Roughly one in 300 Cody Bellinger careers will end up with the all-time home run record. Hot, sexy, algorithmically derived performance forecasts.
But how much do we know about this Szymborski guy anyway?: 24 percent likelihood
ZiPS, at our request, was asked to project player performance 20 years in the future, based on a career that is 52 games old. This was recklessly unfair of us to ask, like asking the world's best doctor to diagnose somebody from three rooms away based only on smell. Of course that doctor would have a huge margin of error. He might call cancer an ear infection; she might call an ear infection cancer.
So it's quite likely that ZiPS has included some phenomenally incorrect assumptions about Bellinger's career, which will certainly not follow the demonstrated trajectories of historical baseball careers. Like, ZiPS probably hasn't factored in Bellinger playing in Coors Field for nine seasons, which he would do if he signed with the Rockies when he hits free agency. It also hasn't factored in Bellinger dealing with chronic back pain after falling off a patio in 2023 while celebrating his new $400 million contract with the Rockies, supposing that happens. Or, more simply, it doesn't really know whether Bellinger made some adjustment in the past three months that makes him truly the greatest hitter ever, or whether pitchers will make some adjustment in the next month that will bother him for the rest of his career. ZiPS attempts to factor in the small likelihood of all these things at once; but most of them won't happen, and the one or two that do happen will throw Bellinger's trajectory fantastically off course in one direction or another.
So we know the 0.3 percent figure is almost certainly wrong. It might be too low, or it might be too high. But there's a lot more room for it to be wrong on the low end than on the high end, so the uncertainty theoretically favors Bellinger's chances. How much does it favor them? No way of knowing. That's the nature of unknown unknowns. I wrote 24 percent so you'd read these paragraphs.
Probabilities are illusions; reality is binary: 50 percent likelihood
We live this reality only once. He'll either do it or he won't. Reality follows no form.
Definitely, he will: 100 percent likelihood
He's the fastest ever to 22 home runs! An object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. It is up to you to prove that such a force exists, or else I can safely conclude that Bellinger will just keep traveling, unimpeded and at incredible speeds, like space trash.
This is what I think: ??? percent
Besides the obvious, there's one big obstacle to taking Bellinger's chances seriously: His debut, for career-records-chase purposes, didn't come early enough. Yes, he's young -- this is his age-21 season -- but he's not that young, and "the fastest to 22 home runs" record should really, in fairness, start at birth.
By that standard, Bellinger is in rare company, but he hasn't set any "fastest" records. Mel Ott hit 86 homers through his age-21 season. Fifteen players hit at least 50, which is the outer range of what Bellinger might be expected to do this year. Those 15 are mostly elite players who had elite careers -- Alex Rodriguez, Ted Williams, Mickey Mantle, Frank Robinson, etc. -- but they all had a head start on Bellinger, and they all ended up hitting fewer than 763 homers. (Compounding this problem slightly, Bellinger has a July birthday, which makes him "old" for an age-21 season. Baseball age accounting starts the year on July 1, so if Bellinger had been born just two weeks earlier this would be his age-22 season. By age, he's not really ahead of, say, Jay Bruce or Jeff Francoeur at this stage of his life.)
But, but, but. He is ahead of Barry Bonds, so there is a physically possible path to 762 from where he's starting. And, crucially, Bellinger, like Bonds, is a product of a particular era, and we can't say anything yet about what that era will be like. If the ball is juiced, and stays juiced, then realistic expectations for Bellinger would go up. Bellinger is built to slug, and he's playing in an era that is built for slugging. As Bonds' record chase showed us, records often tell us as much about the era as the player. And for all the challenges of projecting Bellinger 10 years out, it's a cinch compared with projecting the sport itself 10 years out.
Realistically, I'd say his chances are something like half of 1 percent. Until he slumps, though, it's worth at least a few weeks spent being unrealistic. History rarely gives us such a good opportunity to get in on the ground floor.