After the philosophy class, Klein had a feeling as though he hadn't slept in three days. His mind was filled with names and concepts like skepticism, metaphysics, a priori and a posteriori, nominalism, Roselle socialism, existentialism, and positivism.
If it wasn't because the original Klein had studied history, which included some mastery of philosophy, he doubted that he had the ability to last through the lesson. This wasn't his college lessons on Earth; they were one-to-one, making it impossible for him to sleep, daydream, or read novels on his cellphone when he didn't understand the content.