"What interested me above all was the relationship of these substances to productivity. It has been my experience, however, that creative achievement requires an alert consciousness, and that it diminishes under the spell of drugs. On the other hand, conceptualization is important, and one gains insights under the influence of drugs that indeed are not possible otherwise. I consider the beautiful essay that Maupassant has written about ether to be such an insight. Moreover, I had the impression that in fever one also discovers new landscapes, new archipelagos, and a new music, that becomes completely distinct when the "customs station" appears. For geographic description, on the other hand, one must be fully conscious. What productivity means to the artist, healing means to the physician. Accordingly, it also may suffice for him that he sometimes enters the regions through the tapestries that our senses have woven. Moreover, I seem to perceive in our time less of a taste for the phantastica than for the energetica—amphetamine, which has even been furnished to fliers and other soldiers by the armies, belongs to this group. Tea is in my opinion a phantasticum, coffee an energeticum—tea therefore possesses a disproportionately higher artistic rank. I notice that coffee disrupts the delicate lattice of light and shadows, the fruitful doubts that emerge during the writing of a sentence. One exceeds his inhibitions. With tea, on the other hand, the thoughts climb genuinely upward."
Ernst Jünger to Albert Hoffman (Private Correspondence)