In a peer-to-peer (P2P) overlay network, a peer process (peer) communicates with other peers and manipulates objects like databases in the peers. It is critical to obtain service information on what peers support what service. In a fully distributed, unstructured??P2P network, there is no centralized coordinator. It is critical for a peer to identify which acquaintance is trustworthy since acquaintances may support obsolete service information and may be faulty. There are subjective and objective types of the trustworthiness of each acquaintance. In the subjective approach, a peer obtains the trustworthiness of an acquaintance by itself through communicating with an acquaintance. On the other hand, a peer takes trustworthiness opinions on an acquaintance from other peers. In this paper, a peer only takes opinions of trustworthy peers by excluding faulty peers. A peer has to decide on which trustworthiness type is taken. In this paper, we postulate the more the peer is confident of its trustworthiness opinion, the more the subjective trustworthiness is taken into account.