subjectivity

n. subjectiveness, state of being subjective, condition of relying upon one's own personal judgement, lack of objectivity

In reason, subjectivity refers to the property of perceptions, arguments, and language as being based in a subject's point of view, and hence influenced in accordance with a particular bias. Its opposite property is objectivity, which refers to such as based in a separate, distant, and unbiased point of view, such that concepts discussed are treated as objects.
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Subjective /sub·jec·tive/ pertaining to or perceived only by the affected individual; not perceptible to the senses of another person. [more]Subjectivity - Community and Resources

Noun
1. judgment based on individual personal impressions and feelings and opinions rather than external facts
(synonym) subjectiveness
(hypernym) judgment, judgement, sound judgment, sound judgement, perspicacity

(n.)
The quality or state of being subjective; character of the subject.