In the short story "Marriage is a Private Affair" by Chinua Achebe, the theme of tradition versus individual choice is explored through the conflict between a young man named Nnaemeka and his father, Okeke. Nnaemeka has fallen in love with a woman named Nene and wants to marry her, but his father insists that he marry a woman from their own tribe, the Ibo.
At the beginning of the story, Okeke is portrayed as a traditionalist who values the customs of his tribe above all else. He is deeply offended when Nnaemeka tells him that he intends to marry a woman from another tribe, and he refuses to even consider the idea. He tells Nnaemeka that he has already chosen a wife for him, and that he must marry her according to tradition.
Nnaemeka, on the other hand, is a modern young man who values individual choice and self-determination. He has fallen in love with Nene and wants to marry her, regardless of what his father or anyone else thinks. He believes that love is more important than tradition, and that he has the right to choose his own wife.
The conflict between Nnaemeka and Okeke comes to a head when Nnaemeka decides to go ahead with the marriage despite his father's objections. Okeke is furious and disowns his son, declaring that he is no longer a part of the family. Nnaemeka, however, remains resolute and goes through with the wedding, choosing to follow his heart rather than his father's expectations.
In the end, "Marriage is a Private Affair" suggests that individual choice and self-determination are more important than tradition. While tradition can be an important part of one's cultural identity, it should not be used to control or limit an individual's freedom to make their own decisions. In the case of Nnaemeka and Nene, their love for each other triumphs over the expectations of their families and their respective tribes, and they are able to marry and start their own family on their own terms.