In his "Meditations on First Philosophy," René Descartes tried to answer that very question, demolishing all his preconceived notions and opinions to begin again from the foundations.
Di pirtûka "Meditations on First Philosophy," René Descartes  hewil dike bersiv bide gelek pirsan. Hemû raman û mefhûmê kevin radike, ji serî dest pê dike.