The security of mobile ad hoc networks (MANETs) is challenging due to their distributed nature, which makes them vulnerable to various forms of attacks. To address these issues, reputation and trust management systems (RTMS) have been developed to identify and mitigate abnormal behavior of nodes in the network. However, most existing RTMS systems in MANETs focus on punishing uncooperative nodes, which can lead to energy depletion among the nodes. To overcome this challenge, this paper presents a robust Dirichlet reputation and trust management system that models the reputation and trust of nodes in the network while considering candor, without compromising network security. The proposed RTMS employs Dirichlet probability distribution to model the individual reputation of nodes, and the trust of each node is computed based on its actual network performance and the accuracy of the second-hand reputations it provides about other nodes. Additionally, the paper proposes a novel candor two-dimensional trustworthiness evaluation technique that categorizes node behaviors based on their evaluated total reputation and trust values. Simulation results indicate that the proposed technique encourages and supports nodes that continuously contribute to the network, even when their energy levels decrease.