Em-dash

In Emily Dickinson's poem "I dwell in Possibilities", one can see and notice the unusual amounts of the dashes that she has used. One might think she was trying to censor out something or one might think it's just something that she was obsessed with. But, these dashes are used to be much meaningful than that.
Dickinson's em-dash does a trick of sewing the lines of the poem all together. For instance, the first part where she wrote "I dwell in Possibility--; A fairer House than Prose--; More numerous of Windows--; Superior--for Doors--," she introduces the readers her world of thoughts by leading the readers from whole view of the world zooming to the details of the "House". The "Possibility" would be a name for that imaginary place where she likes to wander and dream because unlike the "Prose," her "House" has more options of "Windows" to seek out beyond the reality. There are no limits in her "House".
Then, she continues this process by continuing the description of the house. She connects the last phrase of the "Doors" with the "Of Chambers as the Cedars--; Impregnable of Eye--; And for an Everlasting Roof; The Gambrels of the Sky--." The house's chambers would be containing very important and precious to her behind the doors, which can be opened only by her. The doors that are made out of cedars suggest that the author treasures:ideas and dreams. The "Everlasting Roof" shows again that there's no end to this "House". There's no closure. It's all opened up for anything and everything that can come in and out. The gambrels would be someplace she would hang her thoughts just in case of losing them.
The last part of her poem is really focused on her but in the world she's been talking about. She continues with "Of Visitors--the fairest--; For Occupation--This--; The spreading wide my narrow Hands; To gather Paradise--." This time, she uses the dashes to lead the readers what she does and how she reacts to the event. The "Visitors" she welcomes by "spreading wide [her] narrow Hands" would be her new thoughts that are brought in to her "House" just as how she would welcome visitors in the real world. She gladly welcomes them with no hesitation because they are the same thing as "Paradise" for her. At the end of the poem, she leaves the dashes as if for the word to echo.
Overall, the poem contained the dashes to continue and make connection with each other in their parts and make three different parts into one whole piece of artwork. The end of the poem is just left to hang to make the reader assume that there's more than what she has mentioned in her world of thoughts.