How Can You Deny What You Have Seen

Acts 4:13-16

13  Now when they saw the boldness of Peter and John, and perceived that they were unlearned and ignorant men, they marvelled; and they took knowledge of them, that they had been with Jesus. 
14  And beholding the man which was healed standing with them, they could say nothing against it. 
15  But when they had commanded them to go aside out of the council, they conferred among themselves, 
16  Saying, What shall we do to these men? for that indeed a notable miracle hath been done by them is manifest to all them that dwell in Jerusalem; and we cannot deny it.