A poem that calls itself "* * *" has declined to tell you what it is about, and Perelman's lines keep that reticence. They open with a flat, almost comic fact: "The shape of his / head is not the shape // of the world." Nobody would argue otherwise, so the statement has to mean something beyond geometry. Taken as a claim about a mind, it says that what a person carries in his skull is not a copy of reality. The next sentence stays dry and slightly mocking: "It satisfies itself // there." The head is content inside its own limits, and the poem seems to watch this contentment with amused suspicion.
The line breaks do much of the thinking. "The shape of his" stops on a pronoun and makes us wait for the noun. "Head" arrives at the start of the next line, so the head is quite literally set up as the thing to be measured. Then "the shape" ends one line and "of the world" begins the next, and the large noun comes in only after a gap, as if the world were being approached from outside. The stanza break before "there" is the sharpest move. The single word sits alone, a small shut door. Whether "It" refers to the head or to its shape is unclear, and that ambiguity is part of the joke, since a head and its shape are both self-satisfied here.
Then the poem swerves. "Have some grapes. Two // breasts." The voice becomes an offer, a host's casual courtesy, and "Two" dangles at the end of its line so that we expect another object of the same kind. We get breasts. The leap makes sense through shape, because grapes and breasts are both round, and roundness is the poem's quiet link. Grapes are offered, breasts are counted, and each is a small, tactile, bodily thing that no theory of the head can hold. "Breathing behind them" adds a living person behind the image, so the body stops being a still life and becomes someone present. The fragments, with no verbs to organize them, read like items arriving in a mind faster than it can sort them.
"Ships / just back out" is the most open phrase. It might mean ships that have only just returned, or ships easing backward out of harbour, or even a shrug, "just back out," as if retreat were the easy option. The poem does not choose. What matters is that the ships bring the wide world into view after the intimate images of fruit and flesh. The last sentence then pulls everything inward: "He makes / the round in his head." A "round" can be a circuit, a sentry's patrol, a round of drinks, a voyage that ends where it began. It also echoes the roundness of grapes and breasts. The head that was said not to match the world now makes its own tour of it, and the poem leaves open whether this is a triumph or a limitation.
Sound supports that uncertainty. There is no rhyme and no regular metre, and the lines are short, mostly three to five syllables, so each one lands with a small bump. The repeated "shape" in the first two lines stresses how fixed the head's outline is. The sibilance of "satisfies itself" makes the self-contentment audible. "Breasts. Breathing behind" pushes the b sound against the reader's lips, which makes the line physical, and "back out" is a short, stopped sound that ends the image of the ships with a click. The syntax is made of brief statements and orders, so the poem sounds like someone talking to himself while handing round a plate.
The poem is significant for how much it does with so little. It states an idea, that thought is not the same shape as the world, and then shows that idea at work. Everything after "there" is the world arriving in fragments, and the final line suggests that the mind will turn those fragments into its own circuit, its own round. Because the poem refuses to explain its connections, the reader has to make them. We link grapes to breasts and ships to the circling head in the same way the man does, which means we are doing what the poem describes. The poem's sense of its own limits is the reason it stays in the mind: it knows a head cannot be the world, and it goes round anyway.