One crucial capability of unmanned systems is their ability to make decisions and inferences like humans. In this paper, we develop a novel logical system that imitates the way humans engage in reasoning with statements possessing varying degrees of ambiguity and unpredictability. Our proposed logical system is constructed using an axiomatic approach with self-evident rules, which allows us to define statemental operations and logical equivalence without the need for a concept of truth valuation. Our logical system includes both statemental algebra and truth calculus, which are designed to manipulate statements and assess their credibility. We believe that our proposed logical system has the potential to enhance the intelligence of unmanned systems.