d’Alembert System

Once roulette became truly popular in Western Europe in the 18th century, people naturally strived to discover strategies that would beat the odds of the casino, and roulette wheel. From this roulette gold fever a simple “negative progression” strategy was derived, which many people still use today. Mathematician Jean Le Round d’Alembert is the inventor of this d’Alembert system.

D’Alembert studied theology among Jansenists, performed law, and studied medicine for a short while. In July 1739 he started his career as a mathematician. He is known for his major contribution to the partial differential equation. With this foundation, he based this system on the ideal that, in the long run, all numbers will fall the same number of times. That’s why this system is central around the idea that if you win a bet, you’re likely to lose the next time, and vice versa. With this in mind, d’Alembert concluded that if you lower your bet after a win and raise your bet after a loss, you can take advantage of this “law of probabilities”.

d'Alembert System2How does the d’Alembert System work?

The following rules should be kept in mind when using the d’Alembert system. Always start with a medium bet amount. A medium bet amount means that you must be able to deduct chips from the bet amount a number of times while still having something on the side. For example, if you play at a table with a minimum limit of 1 euro, with a budget of 20 pounds, you can bet one pound 19 times until you can no longer place bets. This would be a good medium bet. Naturally, you can play with a higher medium bet, but only if your budget is also higher.

In this system, you should bet on only the 50/50 “outside bets”, such as Red, Black, Even, Uneven, and the first or second 18 numbers. Once you have decided what you want to bet, you must stick to this bet throughout this whole game. This is essential. Play this roulette system as follows:

Example

Start by determining your bet amount, and your raise or deduction amount, which should be the same each bet. Place your medium bet on your favourite 50/50 bet. If you win, deduce the chosen amount. If you lose, you add your raise amount. Continue this step throughout the game.

Does the d’Alembert System really work?

Understandably, there are some issues with this system. First of all, the system assumes that the bet red, black, etc is a 50/50 bet. Since there is a green 0, and even two in American roulette, the red or black bet is not really 50/50. It’s actually a 48.65 / 48.65 / 2.7 bet. This mean that even if the system works flawlessly, the casino will still take 2.7% of your bets.

Another problem with this system is that the idea that your chance of losing increases every time you win, and vice versa. The foundation of this system is therefore questionable, since every spin of the roulette wheel is a completely independent event. Even so, as with all strategies, it provides your with a base which increases your chances.