Simplicity
"If you want to entertain knowledge as your guest, you do not need rare furniture, nor numerous servants. Much peace, a little beauty, certain conveniences that save time, are all that is necessary [...] You must reduce matter to the minimum, so as to lighten and liberate the spirit." — Antonin Sertillanges
Contemplation
"Contemplation develops the natural human capacity for knowing through silence, looking inward, pondering deeply, beholding, witnessing the contents of our consciousness and so forth. These approaches cultivate an inner technology of knowing and thereby a technology of learning.” — Tobin Hart
Conversation
"A conversation implies two friends [...] who have a certain affection for each other [...] and so they talk over things together, not try to browbeat one or the other by superior knowledge, or superior intellect, but to investigate together their own problems, their own difficulties, their own personal lives and so on.” — Jiddu Krishnamurti
Hospitality
"To be inhospitable to strangers or strange ideas, however unsettling they may be, is to be hostile to the possibility of truth [...] So the classroom where truth is central will be a place where every stranger and every strange utterance is met with welcome.” — Parker Palmer