One of the first systematic pieces of work which Goethe undertook in order to trace the cause of the Newtonian error was to go through Book I of Newton's Optics, sentence by sentence, recapitulate Newton's experiments and rearrange them in the order which seemed to him essential. In so doing he gained an insight which was fundamental for all future work, and often proved very beneficial in the perfecting of his own methods. His examination of the Newtonian procedure showed him that the whole mistake rested on the fact that 'a complicated phenomenon should have been taken as a basis, and the simpler explained from the complex'. Nevertheless, it still needed 'much time and application in order to wander through all the labyrinths with which Newton had been pleased to confuse his successors'.