Man’s life is innately unpredictable. Our behavior, perspective, and emotions are molded by the random events surrounding us. We possess a natural disposition to mutation. Often we have little control of situations or the manner in which we react. Percy Bysshe Shelley examines the one consistent characteristic of being human in his poem Mutability. The author uses comparison, personification, and alliteration to portray the vast differences of moods, feelings, and reactions that we encounter in our lives.

Shelley opens with a visually stimulating description of the evening clouds. The clouds move brilliantly across the sky and can even veil the light of the moon. The words "speed", "gleam", "quiver" and "streaking" personify the cloud image. They seem constantly fluid, metamorphosing, full of light and are emphasized in line 3 by the word "radiantly." The use of "veil" instead of "covers" instills us with a sense of intentionally shrouded light. This powerful and wondrous sight is eventually extinguished by the darkness. Shelley depicts man’s rapid alterations using the personification of the clouds. While we can shine sparkling light into the world we can also conceal the truth. Situations shape us like the air currents mutate the clouds. Our actions and appearance can conform or we can just disappear from sight as rapidly as the clouds.

The strings of a harp are described as dissonant, which is a musical term for disharmonious. Dissonance is used in music when an intentional feeling of tension and resolution is desired. In the second stanza, each time the wind forces the strings, it causes a response that is unique. Random chaos, or dissonance, is brought to our lives by the wind or the unpredictable torrent what confronts us. Our reactions and feelings, like the harp’s song, never repeat the same series of thoughts or reactions. Even our songs, which are our words, are seldom the same. The alliteration of "frail frame" and "mood and modulation" yields a tone that continues to emphasize contrast. "Frail frame" uses the fricative sound that is full of air, gentle, and delicate in its sound. Man can act delicate and ethereal as a fricative sound. "Mood and modulation" are soothing, steady, warm and buzzy sounds. Man can also contribute by generating wealth or create goods. Both offerings are contrasting in their contribution to the world, yet we are able to yield either, dependent upon the situation and circumstances we are supplied.

The use of "rest", "rise", "feel", and "embrace" holds significance in that each verb becomes more active. Stanza three demonstrates how everything from passive to active can change. Even sleep can be altered by a dream. "Power to poison" alliterates how intensely disturbing a dream can be. Dreaming connotes peace yet the strong words remind us that it also can be sour and frightening. Awaking brings a sense of freshness or newness. Again, the harsh reality of the pollutant thought preoccupies us and spoils the rejuvenation. As thousands of thoughts pass through our mind each minute, one can discomfort us to obsession. The first two lines begin with a two-word sentence, followed by a hyphen. Shelley wants us to pause for the momentary peace of rest. This makes the interruption of the dream so much more pointed. Similarly, the hyphen after "rise" allows us to feel the fresh renewal in awaking until we are altered by a thought.

Because the next line begins with two simple words, we expect that it will follow its predecessors that began with "We." Instead, it continues after a comma to describe contradicting emotions or expressions. "Conceive or reason" come to us as logic or intuition. "Laugh" and "weep" express two divergent feelings. We can dwell on our shortcomings as described by "Embrace fond woe" or think little of them and "cast our cares away." We experience so many varied reactions moved by incidents that transform our lives. The stanza speaks of how divergently we act in everything from the simplistic acts of rest and awaking to the emotionally, mentally and physically taxing actions of considering woes or living carefree.

The word "it" on the next line refers to the result of the aforementioned actions. We explored the movement of the clouds to oblivion, the dissonance and constant variation of the harp’s strings when moved by air, the way we can poison our sleep, pollute the day or adapt our souls to feel drastically different emotions. Whichever we experience, we are always apt to change. The words, "path of departure" symbolize the fact that when presented by a choice we have no idea where it will lead. While we make choices in our lives, we rarely have control over the changes it will bring later down the road. While we think of a road as being static when we chose it, Shelley remind us that even this "still is free" for alteration. In line fifteen Shelley abandons his use of "we" and uses the real subject of his writing; that is man.

Each day is unlike any other day. Today will never be like tomorrow, with one exception. "Mutability" will endure. Ironically, mutability will always endure means that even this randomness can be mutated and may not be consistent. Ultimately unpredictability is the only factor we can count on. Shelley describes man as clouds of nature, a musical instrument and explores the plethora of reactions one can have to a given situation. The capitalization of "Mutability" emphases that it is the defining quality that makes us human.