Frank Jackson first presented the Knowledge Argument in "Epiphenomenal Qualia" 1982). The KA is an argument against physicalism, the doctrine that everything is physical. The general thrust of the KA is that physicalism errs by misconstruing or denying the existence of the subjective features of experience. Physicalists have given numerous responses, and the debate continues about whether the KA ultimately succeeds in refuting any or all forms of physicalism. Jackson himself has recently.