Nine short lines, and nearly every one is a question or a shrug. The speaker tries to remember the last time they were "really truly happy," draws a blank, and ends up asking something more unsettling than where the happiness went: what it even is. The central idea is that the trouble may lie less in a shortage of happiness than in not knowing what happiness is supposed to look like. The poem lives in the gap between "content" and "happy."
The structure works like a small slide downhill. It opens with a question about time, "When was the last time," which assumes there is an answer to retrieve, a memory sitting on a shelf. Then comes failure ("I can't think of a time"), worry ("Is that sad? / Is it bad?"), a shrug ("I'm content I guess"), a hardening ("Never happy"), and a final question that undoes the first. The opening question took the meaning of "happy" for granted. The closing one admits it can't.
That closing question feels earned because of how often the word has been used. "Happy" ends five of the nine lines, and it is the title as well. Say any word that many times and it starts to sound strange, like a sound with the meaning rubbed off. By the time we reach "What is happy?" the word has been worn thin, and the speaker's confusion is something we hear as well as read. The doubled intensifier "really truly" adds to this. It is a childlike phrase, the kind used to swear a promise, and it suggests the speaker is hunting for the genuine article, as if a counterfeit has been on offer. "Content I guess" may be that counterfeit, or it may be something better that the speaker can't bring themselves to value.
The sound of the poem matters as much as its words. The lines are short and conversational, and they break where a hesitation would fall. The first line ends in a comma rather than a question mark, so the question seems to trail off into thought instead of being asked outright. The only rhyme arrives in the couplet "sad" and "bad," and it is almost nursery-rhyme simple. That chime sits oddly against the seriousness of the worry. It also slides from emotion to morality: "sad" describes a feeling, but "bad" sounds like a judgment, as though not being happy might be a failing. After that the rhyme disappears, as if the attempt to tidy the feeling into a pattern has failed.
The most striking move is the step from "not happy" to "Never happy." Logically it is shaky, because the only evidence is "I can't think of a time." A lapse of memory hardens into a verdict on a whole life. The speaker is also lopsided in their certainty. They hedge the positive ("I guess") but not the negative, so doubt attaches to contentment while the bleak word goes unquestioned. Readers might notice that the speaker's own evidence is weaker than their conclusion.
There is almost no imagery, and that absence does real work. In a poem about happiness we might expect a summer afternoon or a laugh shared with someone. Instead there are no objects, no weather and no other people, only an "I" searching an empty room. The poem withholds a picture because the speaker cannot find one to give.
The numbering in the title, "Poem #20," suggests this belongs to a sequence, though that is an inference from the title alone, and the poem stands perfectly well by itself. Its significance lies in its honesty. It doesn't console the speaker or tidy the feeling into a lesson, and it ends on a question mark, which leaves the reader holding the problem. It invites us to ask whether "content" is worth more than the speaker allows, and whether happiness is a steady state or a flash too brief to remember. The plain language makes it easy to enter, and that is part of its force. It is a question many people ask privately, and the poem lets it be asked out loud without decoration.