All truth with malice in it; all that cracks the sinews and cakes the brain; all the subtle demonisms of life and thought

A human being in perfection ought always to preserve a calm and peaceful mind, and never to allow passion or a transitory desire to disturb his tranquility. I do not think that the pursuit of knowledge is an exception to this rule. If the study to which you apply yourself has a tendency to weaken your affections, and to destroy your taste for those simple pleasures in which no alloy can possibly mix, then that study is certainly unlawful, that is to say, not befitting the human mind. (Mary Shelley, Frankenstein)

Kant found the “apices” of the transcendental deduction, as well as the “critique of the subject” upon which they rest, too strenuous for his conceptual powers, weakened as they were by old age. He also considered them dangerous for anyone who happens to embark upon them exclusively or even merely preferentially. Whoever does not restrain himself in view of the consequences of [such] an approach can be driven in almost any direction whatever and will quickly lose his bearings with respect to the entire complex of humanly possible knowledge. (Dieter Henrich, “Identity and Objectivity”)