Natural deduction system in paraconsistent setting: proof search for PCont

This paper continues a systematic approach to build natural deduction calculi and corresponding proof procedures for non-classical logics. Our attention is now paid to the framework of paraconsistent logics. These logics are used, in particular, for reasoning about systems where paradoxes do not lead to the `deductive explosion', i.e., where formulae of the type `A follows from false', for any A, are not valid. We formulate the natural deduction system for the logic PCont, explain its main concepts, define a proof searching technique and illustrate it by examples. The presentation is accompanied by demonstrating the correctness of these developments

Towards Generalised Proof Search for Natural Deduction Systems for logics I⟨a;b⟩

We continue our investigation of the proof searching procedures developed for natural deduction calculus for classical and a variety of non-classical logics. In particular, we deal with natural deduction systems for propositional logics I⟨alpha;beta⟩, where alpha, beta are elements of 0, 1, 2, 3,..., w such that I⟨0;0⟩ is classical logic, proposed by Vladimir Popov. We aim at generalising the concept of an inference for these systems that is fundamental to proof searching technique for these logics

Tackling Incomplete System Specifcations Using Natural Deduction in the Paracomplete Setting

In many modern computer applications the significanceofspecificationbasedverificationiswellaccepted.However, when we deal with such complex processes as the integration of heterogeneous systems, parts of specification may be not known. Therefore it is important to have techniques that are able to cope with such incomplete information. An adequate formal set up is given by so called paracomplete logics, where, contrary to the classical framework, for some statements we do not have evidence to conclude if they are true or false. As a consequence, for example, the law of excluded middle is not valid. In this paper we justify how the automated proof search technique for paracomplete logic PComp can be efficiently applied to the reasoning about systems with incomplete information. Note that for many researchers, one of the core features of natural deduction, the opportunity to introduce arbitrary formulae as assumptions, has been a point of great scepticism regarding the very possibility of the automation of the proof search. Here, not only we show the contrary, but we also turned the assumptions management into an advantage showing the applicability of the proposed technique to assume-guarantee reasoning. Keywords - incomplete information, automated natural deduction, paracomplete logic, requirements engineering, assumeguarantee reasoning, component based system assembly

Natural Deduction in a Paracomplete Setting

In this paper we present the automated proof search technique in natural deduction paracomplete logic. Here, for some statements we do not have evidence to conclude if they are true or false, as it happens in the classical framework. As a consequence, for example, formulae of the type p_:p, are not valid. In this paper we formulate the natural deduction system for paracompletelogic PComp, explain its main concepts, define proof searching techniques and the searching algorithm providing examples proofs

Automating natural deduction for temporal logic

We present our recent work on the construction of natural deduction calculi for temporal logic. We analyse propositional linear-time temporal logic (PLTL) and Computation Tree Logic (CTL) and corresponding proof searching algorithms. The automation of the natural deduction calculi for these temporal logics opens the new prospect to apply our techniques as an automatic reasoning tool in the areas, where the linear-time or branching-time setting is required

On the Complexity of the Natural Deduction Proof Search Algorithm

We present our first account of the complexity of natural deduction proof search algorithms. Though we target the complexity for natural deduction for temporal logic, here we only tackle classical case, comparing the classical part of the proof search for temporal logic with the classical analytical tableau

Paracomplete logic Kl: natural deduction, its automation, complexity and applications

In the development of many modern software solutions where the underlying systems are complex, dynamic and heterogeneous, the significance of specification-based verification is well accepted. However, often parts of the specification may not be known. Yet reasoning based on such incomplete specifications is very desirable. Here, paracomplete logics seem to be an appropriate formal setup: opposite to Tarski’s theory of truth with its principle of bivalence, in these logics a statement and its negation may be both untrue. An immediate result is that the law of excluded middle becomes invalid. In this paper we show a way to apply an automatic proof searching procedure for the paracomplete logic Kl to reason about incomplete information systems. We provide an original account of complexity of natural deduction systems, leading us closer to the efficiency of the presented proof search algorithm. Moreover, we have turned the assumptions management into an advantage showing the applicability of the proposed technique to assume-guarantee reasoning

A Simpler formulation of natural deduction calculus for linear-time temporal logic

The paper continues our studies of natural deduction calculus for the propositional linear-time temporal logic PLTL. We present a new formulation of natural deduction calculus for PLTL. The system is shown to be sound and complete. This new formulation is simpler than the previous one, and this fact is believed to be crucial for possible appli cations of our technique as an automatic reasoning tool in a deliberative decision making framework across various AI applications

Natural deduction calculus for computation tree logic

The authors present a natural deduction calculus for the computation tree logic, CTL, defined with the full set of classical and temporal logic operators. The system extends the natural deduction construction of the linear-time temporal logic. This opens the prospect to apply our technique as an automatic reasoning tool in a deliberative decision making framework across various applications in AI and computer science, where the branching-time setting is required