Anchor: No observer can enter a scene without preconceived ideas, but they can be set aside.
Entailed: People cannot have zero biases, but they can try to overcome them.
Contradiction: Zeros personal bias is the assumed state of being, for many people.
Contradiction: This study is about a new heart disease medication.
Contradiction: Madonna is pregnant. 
Contradiction: They hate things like that.
Contradiction: Deficit-financed tax cut effects depend on whether most parents are strategic or altruistic.