I was brainstorming some more about the indecisiveness and obscurity about what is said of type 9s. This quote from the book/movie "Girl Interrupted" by Susanna Kaysen came to mind:
Susanna Kaysen: I'm ambivalent. In fact that's my new favorite word.
Dr. Sonia Wick: Do you know what that means, ambivalence?
Susanna Kaysen: I don't care.
Dr. Sonia Wick: If it's your favorite word, I would've thought you would...
Susanna Kaysen: It *means* I don't care. That's what it means.
Dr. Sonia Wick: On the contrary, Susanna. Ambivalence suggests strong feelings... in opposition. The prefix, as in "ambidextrous," means "both." The rest of it, in Latin, means "vigor." The word suggests that you are torn... between two opposing courses of action.
Susanna Kaysen: Will I stay or will I go?
Dr. Sonia Wick: Am I sane... or, am I crazy?
Susanna Kaysen: Those aren't courses of action.
Dr. Sonia Wick: They can be, dear - for some.
Susanna Kaysen: Well, then - it's the wrong word.
Dr. Sonia Wick: No. I think it's perfect.
I was also thinking about what it means to have an identity, a personality...a question wolfy posed earlier. What qualities make those things up?
I started off by looking at the dictionary.com definition for both words and then by searching wikipedia for any other "clear" insight on what these may consist of:
i·den·ti·ty
   /aɪˈdɛntɪti, ɪˈdɛn-/ Show Spelled[ahy-den-ti-tee, ih-den-] Show IPA
–noun, plural -ties.
...
2.the condition of being oneself or itself, and not another: He doubted his own identity.
...
5.the sense of self, providing sameness and continuity in personality over time and sometimes disturbed in mental illnesses, as schizophrenia.
Medical Dictionary
iden·ti·ty definition
Pronunciation: /ī-ˈden(t)-ət-ē, ə-ˈ/
Function: n
pl -ties ; 1 : the distinguishing character or personality of an individual
2 : the relation established by psychological identification
per·son·al·i·ty
   /ˌpɜrsəˈnælɪti/ Show Spelled[pur-suh-nal-i-tee] Show IPA
–noun, plural -ties.
...
Psychology .
a.the sum total of the physical, mental, emotional, and social characteristics of an individual.
b.the organized pattern of behavioral characteristics of the individual.
4.the quality of being a person; existence as a self-conscious human being; personal identity.
5.the essential character of a person.
Medical Dictionary
per·son·al·i·ty definition
Pronunciation: /ˌpərs- ə n-ˈal-ət-ē, ˌpər-ˈsnal-/
Function: n
pl -ties ; 1 : the complex of characteristics that distinguishes an individual especially in relationships with others
2 a : the totality of an individual's behavioral and emotional tendencies
b : the organization of the individual's distinguishing character traits, attitudes, or habits
I think this sums up what a personality really is best "the complex of characteristics that distinguishes an individual especially in relationships with others." It is a combination of many characteristics. I think it would be impossible for people to be completely unique in all the characteristics they own, people would not be able to relate to one another in this way. Rather, what makes us unique is the actual combination of these characteristics that we have in comparison to one another, that's what makes one stand out.
When comparing these definitions to the type 9 enneagram description, why can't we just say that one possible or prime characteristic of this type, is said to be one of ambivalence, empathy, middle of the road due to having a broad spectrum of understanding of others and/or flexible likes and dislikes, and relatability. Therefore many preferences, as opposed to none and/or being unsure of one's preferences.