The character of Bertha in "Bliss" by Katherine Mansfield is on the surface a perfect example of a happy picture of motherhood and upper-middle-class life. She and her circle pride themselves on being educated and sophisticated. She believes that as a "modern" woman she is "pals" with her husband and she experiences an odd feeling of bliss for no particular reason.
As we get to know her, though, we see that this picture of her life seen through her own perspective is not grounded in reality. The actual conversation at her party seems silly and superficial rather than sophisticated and profound. The "love" that she claims to have for her daughter only occupies a few minutes of the day and mainly upsets the child, according to the nanny who does all the real work of caring for her. Her relationship with her husband involves no great degree of intimacy or understanding. In a sense, her child and marriage, like her social life, are almost a play world and the "harshness" of Harry and cool mystery of Pearl suggest a different adult reality outside her own imagination.
This story is an example of how appearances can be deceiving - and how impressions and emotions can also be that way. Bertha is a young housewife who imagines herself happy. She is a comfortable home, a husband she respects, and friends that she enjoys. She finds happiness in even the smallest things. She imagines herself to be perfectly content.
However, Bertha allows the appearance of happiness to be deceiving to her own emotions. Because she has the "perfect" household, she assumes she must be perfectly happy. However, her marriage does not have passion and she is not close to either her daughter or those friends she so admires. She doesn't really know what is going on beneath the surface. She allows the picture to determine her gauge for her own feelings.
When she realizes that Harry is having an affair, the picture is shattered, and Bertha doesn't know what to do. If she can't trust the picture - like the pear tree - to tell her that she is happy, how will she know if she is?
The internal and external self dichotomy within Bertha. Bliss is ignorance- she has subconsciously hidden her internal self (from opening) and you can see that this internal self (perhaps taken to extreme ends as a derision for societal oppression) is beginning to come out to the external facade?