Here's the poem:
A cool small evening shrunk to a dog bark and the clank of a bucket -
And you listening.
A spider's web, tense for the dew's touch.
A pail lifted, still and brimming - mirror
To tempt a first star to a tremor.
Cows are going home in the lane there, looping the hedges with their warm
wreaths of breath -
A dark river of blood, many boulders,
Balancing unspilled milk.
'Moon!' you cry suddenly, 'Moon! Moon!'
The moon has stepped back like an artist gazing amazed at a work
That points at him amazed.
Frieda is Ted Hughes' daughter; she is the "you" who is "listening" in line 2 and the "you" who cries "Moon!" in the 2nd stanza. So, we have a poet observing a daughter observing the full moon. And, in the last stanza, the moon is observing them (namely Frieda), like an artist who has just finished a painting.
The metaphysical conceit works on three levels: father observing child; moon observing child; poet observing them all. The first two stanzas are primarily physical; it is the third stanza that transcends the physical and enters the metaphysical. Hence, the moon is personified as an artist who is as thrilled to see Frieda's joy at seeing the full moon poet Hughes is.
It is this symbiosis between nature and man and between poet and subject and artist and subject that allows the poem to go beyond the physical.
The beautiful poem 'Full Moon And Little Frieda' by the poet Ted Hughes challenges reality in the first line where 'the cool small evening shrunk.' Here we as readers get a sense of the space/time dimension - of infinity. The universe is conveyed in the idea of time (the evening) having form that can be altered. The poem reaches out in time from the poet's day to ours as it introduces a 'listener' - we feel like that person could even be us. Time is referred to again in terms of waiting - a spider's web waiting 'for the dew's touch.' Now we arein the present watching the 'unspilled' pails. Then we are in the past for a second where the moon 'has stepped back' to look at a mirror of itself - a little girl who has the sense of wonder, as it has.