Anchor: Here high-domed ceilings drip with stalagtites, and human bones more than 50,000 years old have been found.
Entailed: Human remains have been discovered that are over 50,000 years old.
Contradiction: Human remains less than 100 years have been found here. 
Contradiction: They were nowhere near the main tent.
Contradiction: I feel disturbed at this prospect.
Contradiction: I saw him all the time.  
Contradiction: A business man goes up a briefcase.