Noetics
Noetics is science of understanding. Subject of its study is reality of being, reality and principles of understanding and the borders of understanding of our being. Same as the science of logic, noetics is interested in questions of validity of our thinking, but more than logic, noetics also searches the problem of contents of logical judgements. Equivalent names for Noetics - or better - some parts or streams in Noetics are also known as Critic of understanding, Gnoseology, Epistemology and Criteriology. The first philosopher particularily interested in some acpects of later noetics was Augustinus Aurelius, but real foundators of Noetics were René Descartes, John Locke and Immanuel Kant.
Literature
Augustinus Aurelius: Contra Academicos; Descartes: Meditations; Locke: Human Sense; Hume: Human Sense; Kant: Kritik der reinen Vernunft
Modern Literature
Mercier: Criteriologie general; Vries: Denken und Sein; Steenberghen: Epistemologie; Brunner: Erkenntnisstheorie; Cassirer: Das Erkenntnissproblem; T. E. Hill: Contemporary Theories of Knowledge.