Stockton's The Lady, or the Tiger? is similar to the logic puzzle Knights and Knaves, but cannot be solved with logic. The reader, in deciding the ending, shows something of his or her inner thoughts.
There are several major conflicts present in the story, so we will touch on two: Man vs. Society and Man vs. Destiny.
Man vs. Society: in the world of the story, the punishment of allowing the prisoner to choose his own fate -- marry a stranger or die at the claws of a tiger -- is considered reasonable, fair, and great entertainment.
The institution was a very popular one. When the people gathered together on one of the great trial days, they never knew whether they were to witness a bloody slaughter or a hilarious wedding. This element of uncertainty lent an interest to the occasion which it could not otherwise have attained.
It is described in the text as "semi-barbaric," and would seem today to be completely so. However, in the context of the story, it is completely normal. The princess's lover is subjected to the punishment, and he goes without complaint, but he still seeks to cheat by looking to her for guidance. In this way, he rebels against the Society that finds the game amusing; even if he is killed by the tiger, he has thwarted the game by refusing to play by the rules.
Man vs. Destiny: simply put, any man who would dare to love the princess would be guaranteed a trip to the trial pit. The youth would know this; he fights his Destiny by refusing to be swayed by the possibility of a brutal death.
"...one day the king happened to discover [the affair's] existence. He did not hesitate nor waver in regard to his duty in the premises. The youth was immediately cast into prison..."
Since the punishment is a foregone conclusion, one must conclude that the youth considered his love for the princess and their time together to be an worth his eventual Destiny.