From Andrew Seth, The Development from Kant to Hegel (1882)

“After Schelling’s departure from Jena, we may fancy Hegel watching with dissatisfaction the brilliant but nebulous speculations of his friend, and the extravagance and intellectual frivolity of the minor men in the domain of Naturphilosophie. His deep-seated aversion to all this formless speculation was uttered to the world at last in the famous Preface to the Phaenomenologie des Geistes (1807). There is a bitterness of passion about the weighted sentences, that marks it as an outburst of long pent-up irritation.”