Premise: If you turn right instead of left from O'Connell bridge, you will come to one of Dublin's great architectural masterpieces, the Custom House (Visitor Centre open mid-March mid-November, Monday Friday 10am 5pm, Saturday and Sunday 2pm 5pm; winter, Wednesday Friday only).

Hypothesis: You have to turn left from O'Connell bridge to find the Custom House.
Relation: contradiction