In an early treatise, Attempt to Introduce the Concept of Negative Magnitudes into Philosophy (Versuch, den Begriff der negative Grössen in die Weltweisheit einzuführen, 1763), Immanuel Kant developed a theory about thoughts that are fleeting, negated or cancelled, obscured or darkened. As certain thoughts become clearer, the other thoughts become less clear and more obscured (Verdunkelt). Kant’s concept was influenced by the petites perceptions of Gottfried Wilhelm Leibniz. He invoked Leibniz in establishing that only a small portion of the representations which occur in the soul, as the result of sense perception, are clear and enduring.
Hendrix, John S., "Immanuel Kant: Philosophy of Perception" (2019). Architecture, Art, and Historic Preservation Faculty Publications. 41.