The Four Horsemen of Aberdeen Blackjack

From L-R: James McDermott, Wilbert Cantey, Herbert Maisel, Roger Baldwin.

The name sounds much more dramatic than the picture of the four, very old, men warrants, but their work has certainly caused something of a plague on casino owners, who have indeed gone to war with blackjack advantage players.

Quite simply, if it wasn’t for these four men then perfect blackjack strategy might not exist, and neither would card counting. They are widely accepted to be the very first to come up with a system for playing blackjack, and certainly the first to make their system public knowledge.

The name was given to them in 1965 by Dr Allan N. Wilson when he referred to the men as The Four Horsemen of the Apocalypse in his book, ‘The Casino Gambler’s Guide’; but many people now refer to them as The Four Horsemen of Aberdeen.

Why? Well it all started with a game of cards in an army barracks in Aberdeen, Maryland, USA. The year was 1953 and a young Private with a master’s degree in mathematics just happened to be listening as another solider, tired of playing poker, suggested blackjack and ran through the rules of the game.

Who Were The Four Horsemen of Aberdeen?

Roger Baldwin

Baldwin was the man who got the ball rolling. It was he who overheard the conversation in the barracks and his interest was piqued.

After attending Columbia University and attaining a degree in mathematics, Baldwin joined the army just in time for the end of the Korean war. Had he been stationed anywhere else, blackjack strategy may never have come to be.

There is very little information on Baldwin’s life outside of his blackjack achievements other than he continued to work in applied statistics and data processing, but he never really gambled despite his amazing work.

Wilbert Cantey

Cantey was Baldwin’s Sergeant, and gave him permission to use the base’s ‘adding machines’ as they were known back then – calculators to you and me.

He had been all set for a life as a pastor, even attending the seminary to study scripture, but after hustling people at cards and pool it was decided that he perhaps would be better suited doing something else. He also had a master’s degree in mathematics, and worked as a government researcher later in life.

Cantey died in 2008, just months after being inducted into the Blackjack hall of Fame. He was 77.

James McDermott

Despite studying at Columbia just like Baldwin, McDermott never met the man he would go on to serve with in the army. He too earned a degree in mathematics before his service began, and was enlisted by Baldwin and Cantey when they realised how taught the task was going to be.

In later life, James went on to be an executive at IBM where he worked for 33 years. He died in 2018 aged 88.

Herbert Maisel

The only member of the team without a degree at the time, Maisel was a natural born mathematician, well known amongst his friends and peers as the go to guy for anything to do with numbers. He joined the army straight out of school.

Post military service and creating the first ever blackjack strategy, Maisel went on to teach computer science at Georgetown University – no doubt those computers would have come in very handy back in the 50s!

He passed away in 2019 aged 88.

How the Four Horsemen Created the First Blackjack Strategy

The Aberdeen Proving Grounds wasn’t the sort of army base where soldiers were made to crawl through mud and do drill every day. It was a testing facility where new weapons were developed, manufactured, and trialled, so the sort of soldiers based there were thinkers rather than brawlers.

The trigger for Baldwin’s idea was learning that when playing blackjack in Vegas, the dealer has to draw on 16 and stand on 17 – something that he had never done when playing with friends – and it made him wonder if the rules could be exploited. He did a few rudimentary calculations to see if his idea had legs.

It clearly did, but to work out the best course of action in any given blackjack scenario was an extremely complicated task, so he asked his sergeant for permission to use the base’s adding machines. We would call them calculators these days, but this just goes to emphasise how long ago this was. Computers, AI, and machine learning were the stuff of sci fi novels back then.

That sergeant was Wilbert Cantey who became interested in the idea and agreed to help Baldwin. The job became too much even for two mathematical brains so they enlisted two more gifted privates, McDermott and Maisel.

The Four Horsemen had been brought together, and now spent countless hours scrutinising the cards and recording their results. 18 months of hard work later, they had created a basic strategy for blackjack which explained what the best move was from a statistical point of view in any given situation.

Playing Blackjack to Win

Playing Blackjack to Win ReprintBeing mathematicians, the four men were keen to share their findings and were proud of what they had achieved. Although they hadn’t found a way to tip the odds in the player’s favour, they had all but eradicated the house edge making it an even game over the long term.

What was even more impressive though, especially to those of us born generations later and used to having computers work things out for us, is that they did it all using nothing but their brains, pencils and paper, and a mechanical calculator.

Their findings were first published as an 11 page analytical study in the Journal of the American Statistical Association in 1956, but a year later and after much interest, they had expanded on this and written a full length book: Playing Blackjack to Win.

This book contained a chapter called ‘Using the Exposed Cards to Improve Your Chances’, and in it they described the process of ‘partial casing’. This was the first known reference to the concept that we now know as card counting, although it was nowhere near as sophisticated as it has become these days.

Their strategy though still stands the test of time, with only one or two debateable decisions and even then, in some versions of the game they would be the right call. Playing their strategy today would, at the very worst, give only a few hundredths of a percent in value back to the casino.

Their book went out of print for a long time, but a young man named Edward O. Thorpe got hold of it before it did, and he built on the Four Horseman’s idea to develop a revolutionary card counting strategy that would change blackjack forever. Without the work of these four men though, he may never have gotten off the ground.

Life After Blackjack: Their Legacy

Blackjack Hall of Fame

Visitor7, CC BY-SA 3.0, via Wikimedia Commons

For many years The Four Horsemen were more or less forgotten, certainly unknown by those outside of blackjack playing circles.

None of them went on to do any serious gambling or make any money from their strategy, they didn’t even make a great deal from the sale of their book.

Players that came afterwards, built on their hard work, and took the casinos for millions are the ones who got the glory and the headlines, but without Roger, Wilbert, James and Herbert none of those high rollers would have been able to make their money.

The four men were officially recognised in 2008 when they were inducted into the Blackjack Hall of Fame, and celebrated in person at the 12th annual blackjack ball.

To card counters everywhere these men are legends, even if they never made a penny from gambling themselves, and names like Johnny Chang, Stanford Wong, and Max Rubin have all publicly sang their praises.

In the 50th Anniversary reprint of their book, Edward O. Thorpe himself wrote in his foreword; “To paraphrase Isaac Newton, if I have seen farther than others it is because I stood on the shoulders of giants.”