Answer and Explanation:
"Once upon a time" by Gabriel Okara portrays how society, although it has evolved and become more modern and more efficient, has become futile, made and false. We can see this in the poem, when we realize that the speaker of the poem is a father, who tells his son how the world has changed. At this point, the father begins to remember how people were when he was younger and shows, with nostalgia, that people were more sincere, truthful and friendly. For the father, people used to smile with their hearts and approach without interest and without caring about appearances. The speaker says that currently, people smile with their teeth and not their hearts, that is, they do not smile with emotion, but smile falsely, worried that people are looking and thinking about them.
In this poem, we can see how the price we have to pay for modernity, which on the one hand makes our lives easier, but on the other hand, makes us less human.