and connected to the cute, freckled wall (as if it were a face) to the point where it becomes part of the mirror’s heart. The fact that the mirror even has a heart and that the wall “flickers” makes the situation seem like a flirtatious, romantic relationship.

The second stanza is an extended metaphor, where the mirror compares itself to a lake. Plath also labels sources of dim light—candles and the moon—as liars. Through this metaphor, she emphasizes how they are distorting and deceptive, in contrast to the clear and honest mirror/lake.

The lake is an example of not only extended metaphor but also personification. It actively sees and reflects a woman's face and even considers itself “important to her.” The lake declares,

In me she has drowned a young girl, and in me an old woman
Rises toward her day after day, like a terrible fish.

Drowning is a metaphor for aging; the young girl dies and returns as a hag. Plath ends the poem with the simile “like a terrible fish” to emphasize how repulsive the old woman has become. Ironically, the woman morphs into a nonhuman entity (e.g., the fish) in a reverse form of personification.

A figure of speech in poetry is also known as literary devices or poetic devices. The main figure of speech used in the poem is one of personification.

Personification according to the eNotes site is:

a figure of speech in which abstractions, animals, ideas, and inanimate objects are endowed with human form, character, traits, or sensibilities.

What this means is that non-human things are given traits that only humans typically have. An example of personification would be "the wind is laughing" or "the clouds are screaming". Wind cannot laugh and clouds cannot scream. Only people can laugh and scream.

The entire poem "Mirror", by Sylvia Plath" is a personification poem. The personification is denoted by the title of the poem. Without the title, one could justifiably assume that the poem is about a person given the human characteristics depicted in the poem itself.

Whatever I see, I swallow immediately.

Here, the line refers to a mirror swallowing the reflection seen in the glass. Mirrors cannot swallow anything, but people can. Therefore, this examples the personification used in the poem.

Another figure of speech that exists in the poem is one of hyperbolic language. A hyperbole, as defined by eNotes, is:

obvious and deliberate exaggeration or an extravagant statement.

Basically, a hyperbole is an over-exaggeration of the truth. Here, an example of hyperbolic language is:

Now I am a lake.

The mirror is stating (personification- mirrors cannot state anything) that it is a lake. This qualifies as a hyperbole because a mirror is nothing like a lake- it is small and has no depth (physically). The hyperbole exists because the mirror is describing how deeply one can look into a mirror and it would seem that the mirror is endless and deep.

The last example of figurative speech in the poem is one of a simile. A simile is a comparison between two things using the words "like" or "as".

Rises toward her day after day, like a terrible fish.

The comparison is the image of the woman reflected in the mirror to that of a fish.

When writers use metaphors, they use non-literal language to make connections between two things that aren't otherwise connected.

For example, imagine you said, "He's a dog." You're referring to a man with no standards. He's not literally a dog. He's human.

In "Mirror," Plath definitely uses metaphors. There are a number in the poem.

Take the first few lines as examples:

I am silver and exact. I have no preconceptions.
Whatever I see I swallow immediately
Just as it is, unmisted by love or dislike.

If the speaker is the mirror, then it is not literally true that it swallows things. Images of things pass into mirrors like they are being swallowed, though, and that's the connection. Likewise, mirrors do mist, but the literal mist is water condensing on them. Here, "unmisted by love or dislike" is a metaphor for being emotionally unmoved, or objective. That's how mirrors see things.

“Mirror” by Sylvia Plath is one of the great American lyrical poems.  The poem’s form is free verse. Written in first-person point of view, the speaker is the mirror.  The theme of the poem speaks to the honesty of the mirror and the importance of being like the mirror in a person’s life: looking at a person with complete truthfulness.

The figurative language used in the poem begins with the extended metaphor that lasts the entire poem.  The poem is divided by stanzas into two distinct aspects of a mirror: the actual mirror and a lake.

The first stanza begins with the mirror hanging on a wall reflecting whatever it sees.  It has no choice.  It is not intentionally cruel when it reveals what it actually sees.  The mirror is truthful.  With the correct lighting it sees everything like a “little god.”  The wall across from it is pink and has become a part of the mirror’s heart. When people pass in front of the mirror, it seems as if the wall is flickering.

In the first verse, there many examples of figurative language:

The mirror compares itself to a "little god." This is an example of a metaphor comparing the reflection of the mirror which reflects everything that it sees to a deity.

Personification is used in the line: Whatever I see I swallow immediately
Just as it is…

This gives the mirror the ability to swallow as if it were a person.

In stanza 2, the mirror becomes a lake. 

Every morning, a woman looks at her reflection in the lake.  As time goes by, she no longer likes what she sees.  She uses the tools of a woman to hide the aging process.

Now I am a lake. A woman bends over me,
searching my reaches for what she really is.
Then she turns to those liars, the candles or the moon.
I see her back, and reflect it faithfully

The false compliments are represented by the dim lighting, moonlight, and the cosmetics. Finally, now when she looks into the lake, she sees old age coming toward her like a terrible fish.

A metaphor is used when the mirror compares the false compliments to the light of the moos and the efforts of the woman to hide her aging with the light of the candles.

A simile is used to compare the mirror as it reflects the aging woman to a "terrible fish."

The entire poem "Mirror" is an extended use of personification. The poem is in first-person, with the speakers embodying the reflector concept in two different ways. The speaker in the first stanza is an actual mirror, and the one in the second stanza is a lake.

In stanza one, the mirror speaks of its (vertical) position hanging on the wall, silver and four-cornered. It mentions its heart but also says its reaction is "unmisted by love or dislike." It refers to reflection as "swallowing."

The second stanza's speaker is a lake, a different kind of mirror, in horizontal position as a "woman bends over" it. This lake reflects "faithfully," in contrast to light from candles, which are "liars." Rather than say that the woman is aging, the mirror says she has "drowned" a girl in it. The old woman she has become rises out of the lake like a fish.

Before one can paraphrase a poem, it's best to fully understand its meaning, and then work your way backward from there.

Let's look at the poem's most significant verses: 

I am silver and exact. I have no preconceptions.
Whatever I see I swallow immediately
Just as it is, unmisted by love or dislike.

A mirror reflects a clear, undistorted image. As the speaker refers to themselves as the mirror, they know that what they see is true and that there is no external force at play. The speaker believes he or she is clearsighted.

Nothing has caused them to doubt their identity, they have accepted all of their traits without dwelling on whether they consider them flaws or advantages, and they have no plans to adjust their identity in order to fit an idea. They are stable and self-assured, and what they see is simply the truth. This perspective is what the mirror represents. 

The poem then goes on to say:

Most of the time I meditate on the opposite wall.
It is pink, with speckles. I have looked at it so long
I think it is part of my heart. But it flickers.
Faces and darkness separate us over and over.

This is the beginning of the speaker’s identity crisis. The speaker was convinced that what they’d constantly seen—the pink, speckled wall across from it—was all that there was and that there'd ever be, i.e., a simple and unchanging life of satisfaction. 

The flickering, caused by faces and darkness, is when the speaker begins to doubt what they see. They interrupt the mirror's point of view—the only thing the speaker had come to know. Looking at the poem as a metaphor, they could be speaking respectively of the people coming in and out of their life and the development of a deep depression or a tragic event. This is only speculation, but it’s important to make connections in order to better understand a poem—especially one from the apparent point of view of an inanimate object.

Now I am a lake. A woman bends over me,
Searching my reaches for what she really is.
Then she turns to those liars, the candles or the moon.

Here, Plath describes a lake as a distorted and confusing reflection. The woman who seeks to find herself in the lake’s reflection will not see her true self, because this time there are external forces at play—moonlight and candlelight, reflected in the lake along with the woman's face. 

I see her back, and reflect it faithfully.
She rewards me with tears and an agitation of hands.

The transition from being a mirror to a lake could represent internal struggles as a person in an identity crisis, going from a routine contentedness in their own life to a constant experience of sorrow and frustration no matter how hard they try to go back to normal by "faithfully" reflecting the woman's back—who obviously ignores their efforts.

The emergence of the woman, however, can also be seen as a representation of the speaker's internal struggles. This is shown through the following lines:

I am important to her. She comes and goes.
Each morning it is her face that replaces the darkness.
In me she has drowned a young girl, and in me an old woman
Rises toward her day after day, like a terrible fish.

The speaker describes the lake as an important element in this woman's life in order to show that understanding one's identity is important. The woman returns again and again, but still she cannot truly see all of herself among the flickering moonlight and candles, and this agitates her, until eventually, in her efforts, she loses the parts of herself she knew—represented by the drowning of a young girl, as symbolism of the loss of youth and joy—and sees only the version of herself she hates—an old woman—jumping back out at her "like a terrible fish."

It's more evident now that the poem tells the story of a sequential descent into crisis, going from the emerging insecurities of the speaker (faces and darkness), to a complete and significant change in form (mirror to lake), to observing and affecting others in their search for their identity (the troubled woman). 

With this analysis at hand, it is much easier to paraphrase such a powerfully complex poem by keeping the essential elements of its theme at the forefront.

For example: 'The Mirror' by Sylvia Plath is a metaphorical expression of an identity crisis, using the clear and undisturbed reflection of a mirror and the chaotic, deceitful reflection of a lake to symbolize a shift from a stable sense of self to a sense of self muddled by external forces. This is even further represented through the emergence of a woman in the poem who cannot seem to find a whole and truthful image of herself in the lake's reflection, thus emphasizing the speaker's identity crisis through their uselessness as a source of reflection and providing a manifestation of the speaker's feelings through the woman's struggles.

[Please remember that analysis of a poem is subjective, and this answer is based upon what I perceive. Also note, however, that any interpretation of a piece of literature—to my mind—is valid as long as you can support your viewpoint with logical reasoning from the text. With this in mind, be confident in your ability to analyze poetry.]

Generally, a paradox is a literary device that states a truth that seems contradictory and untrue at first glance. However, the explanation of paradox also describes more subtle forms of the device, very different than the one noted above. The definition goes on to state...

Sometimes [paradox] is applied to a self-contradictory false proposition.

Studying this kind of paradox, we see that truth is not always a part of all of its forms. Based upon the author's troubled life, this darker form of paradox might seem a more appropriate form of the device to use. But as subtle as the forms of paradox might be, so are Plath's artful perceptions and her implementation of them into her work.

Look to Sylvia Plath's poem "Mirror." Line four is paradoxical:

I am not cruel, only truthful...

I find this a paradoxical statement. How can one tell the truth and not be cruel in some circumstances? By nature, many truths are things that people would rather not hear. From the start, we should look for a "self-contradictory false proposition."

The mirror that is speaking in the poem has been personified—given human characteristics—and so it cannot be accepted now as truthful and not cruel. The presence of personification robs the mirror of its impartiality and credibility. The identification of personification can be found in the following:

I have looked at it so long
I think it is a part of my heart. But it flickers.
Faces and darkness separate us over and over. (7-9)

How can a mirror have a heart? This in itself seems paradoxical: how can an inanimate object have feelings? When the mirror is personified, then its statement regarding its complete objectivity is called into question.

Knowing as we do that mirrors must reflect what they see, and couldn't possibly hold judgment as inanimate objects becomes irrelevant when our narrator is a mirror.

By the poem's end, the mirror reports what it sees, but it passes judgment. When truth is presented, there is only the statement of fact—no judgment.

Each morning it is her face that replaces the darkness.
In me she has drowned a young girl, and in me an old woman
Rises toward her day after day, like a terrible fish. (16-18)

The mirror states that the woman has wasted her youth studying her image in the mirror, looking for signs that she is aging. This is a subjective observation. The mirror's narrative is now biased. It speaks of the woman's face now—but that the mirror at one time reflected the image of a young girl...that the woman has drowned (a harsh and emotionally-charged word choice). The face that the mirror reflects back (it says) is old. The mirror goes on to compare the visage of the woman rising into the mirror's sight each day to that of a "terrible fish." This is a clear example of being cruel, which the mirror claimed it could not be at the poem's beginning.

The clues we find to identify this kind of paradox are glaringly obvious in the diction (word choice) the author employs. In life, hearing the truth may sometimes feel like cruelty. However, what the mirror observes is subjective, judgmental and unkind. By definition, the form of paradox used in this poem "presents a self-contradictory false proposition."

There are two clear metaphors in Sylvia Plath's poem "Mirror." Some readers may see an additional metaphor in the use of the word "swallow" in line two, which suggests that the mirror is a creature capable of swallowing things, but this idea is not developed. Other readers may regard the entire poem as a metaphor describing, for instance, a person so passive that she only reflects whatever is before her. However, the poem works just as well, and arguably better, when interpreted as the description of a literal mirror.

The first undoubted metaphor comes when Plath describes the mirror as "The eye of a little god." This image recalls the household gods of the Romans, the Penates, who would be worshipped at small domestic altars. Worshippers look anxiously into the mirror, hoping that it will be kind, but this god tells only the truth.

The second stanza of the poem is an extended metaphor in which the mirror is described as a lake. The strangeness of this metaphor comes from the fact that the lake in question is being used as a mirror. Since the woman is merely looking into the lake to see her own reflection, it is, at first, difficult to see what the metaphor adds to the poem. This question is answered in the dramatic final image, when her reflection rises from the depths of the lake "like a terrible fish." It shows her as an old woman rather than the young girl she imagines herself as.

Keep in mind the definition of figures of speech, which is language that is not meant to be literal, but makes a comparison between two things which are not alike.  Figures of speech include both similes and metaphors.

The two most obvious figures of speech in this poem are the opening lines of each stanza:

I am silver and exact.
Now I am a lake.

In order to decipher what these metaphors may mean, you can answer a few questions:

1. Who is the "I" here, or who is speaking?
2. What are some things you think about when you think of a mirror and a lake?  What attributes of a mirror and a lake might the speaker be comparing to herself?
3. What details from the poem itself can help you prove your ideas in question #2?
4. How are a mirror and a lake similar but different?  How might the differences between a mirror and a lake show changes the speaker goes through?
5. What details from the poem can help you prove your ideas in question #4?

Remember that though poetry is often ambiguous and certainly subjective to a reader's point-of-view, you should always use textual clues to help support your ideas.  If you can answer the above questions, you most certainly will have identified the figures of speech in this poem.  Additionally, you will have brought yourself into the interpretation, which is exactly what poetry calls for.