The term for a conclusion drawn strictly from personal belief is "opinion." Synonyms for the word "opinion" include: "point of view," "judgement," and "assessment." The opposite of an opinion is a "fact."
Different disciplines use different words when distinguishing opinion from fact. For example, in science, an opinion is called a "hypothesis." In math, an opinion becomes an "estimation" or an "educated guess." Conversely, a fact is a statement that can be proven and stands apart from feelings and morals. An example of a fact is that there are 50 stars on the flag of the United States of America.