This is an interesting question. There are several ways of looking at the outcome. It might be said that neither of the men actually won or lost the bet, because the lawyer didn't collect the two million rubles and the banker didn't lose the two million rubles. Morally speaking, however, it would appear that the lawyer won the bet and the lawyer decided to let the banker "off the hook" by walking out the door five hours before the deadline.
The banker seems to be acknowledging that he lost the bet by his thoughts and behavior on the night before the term of imprisonment expired. He sneaks into the prisoner's room for the first time in fifteen years with the intention of murdering him after keeping him in solitary confinement for all that time. The banker himself would acknowledge that he had lost the bet, and the lawyer would probably assert that he had won it, although he disdained to collect the money.
The bet itself is hard to understand. Initially the two men were arguing about the relative cruelty of capital punishment versus life imprisonment. This is the pertinent dialogue.
"The death sentence and the life sentence are equally immoral, but if I had to choose between the death penalty and imprisonment for life, I would certainly choose the second. To live anyhow is better than not at all."
A lively discussion arose. The banker, who was younger and more nervous in those days, was suddenly carried away by excitement; he struck the table with his fist and shouted at the young man.
"It's not true! I'll bet you two million you wouldn't stay in solitary confinement for five years."
"If you mean that in earnest," said the young man, "I'll take the bet, but I would stay not five but fifteen years."
In the first place, the young lawyer doesn't have anything like two million to put up. It isn't really a bet. The banker has nothing to gain He probably regrets getting involved in such a contest as soon as he has committed himself. He not only stands to lose a fortune, but he has to keep the lawyer in comfort for as long as the young man chooses to stay. He provides his meals and even offers to serve him wine. But how did the question of "life imprisonment" suddenly and inexplicably turn into fifteen years of solitary confinement. Men serving life sentences are not sentenced to solitary confinement too.
It was agreed that for fifteen years he should not be free to cross the threshold of the lodge, to see human beings, to hear the human voice, or to receive letters and newspapers. He was allowed to have a musical, instrument and books, and was allowed to write letters, to drink wine, and to smoke....He might have anything he wanted--books, music, wine, and so on--in any quantity he desired by writing an order, but could only receive them through the window.
Chekhov had to change the argument from capital punishment versus life imprisonment to capital punishment versus fifteen years of solitary confinement. It is hard to detect the slight of hand by which he does this, but he could hardly have a character serving a life sentence, because he would have to die in prison in order to win. The bet is "wild and senseless" enough as it is, but no one would bet he could spend life in a typical prison without the amenities the banker was providing.
"The Bet" is not a typical Chekhov story. He does not usually have surprise endings or even resolutions. "The Lady with a Pet Dog" is more "Chekhovian."
In my opinion the lawyer won the bet, by abandoning the money just a few hours before the end of the bet. Through his readings he experienced the world and could clearly see the weakness of mankind. In fact, the lawyer purposefully lost the bet and escaped from the confinement as he began to despise wordly possessions.
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