Why was Vincent not named after his father, Antonio?

The answer lies in the societal context of the film "Gattaca," where genetic engineering and eugenics play significant roles in determining one's perceived worth and potential. Vincent was not named after his father, Antonio, because he was conceived naturally and was deemed genetically inferior due to the presence of a congenital heart defect. In the world established by the film, the firstborn son's fitness and abilities often influence naming conventions, with families expecting their first child to be the pinnacle of genetic quality and achievement. The notion that Vincent, despite being the first son, was seen as unworthy of bearing his father's name due to his perceived genetic flaws aligns with the film's exploration of identity, societal expectations, and the stigma surrounding those who are considered "in-valid" in a highly stratified genetic society. This context makes it clear why Vincent's parents would choose to name him separately from his father, emphasizing the harsh realities faced by those who are not genetically engineered or deemed "perfect."