Though I think, after Augustine Casiday's recent work, that any suspicion of Evagrius should be set aside, I would argue that even those who are still a bit uneasy about him can and should benefit from his original and path-breaking insights into the role of the mind and the destructive power of thoughts--1500 years before Freud and modern psychology. I thought of Evagrius and his insights into the logismoi or disordered thoughts when listening last weekend to a fascinating and moving interview on NPR with Martin Pistorius and his harrowing descent into massive disability whereby he was unable to move or communicate, but still had an active mind--a mind that began malevolently to work against him, assaulting him with dark and despairing thoughts of his hopelessness and worthlessness. How cruel those thoughts can be! It is little short of miraculous that he has made the dramatic recovery he has, as recounted in his recent memoir, Ghost Boy: The Miraculous Escape of a Misdiagnosed Boy Trapped Inside His Own Body.
There are many recent studies on Evagrius, but three in particular address the thoughts and the temptation of despair: George Tsakiridis, Evagrius Ponticus and Cognitive Science: A Look at Moral Evil and the Thoughts. (I interviewed George here.) In addition, there is David Brakke's Evagrius Of Pontus: Talking Back: A Monastic Handbook for Combating Demons and then Gabriel Bunge's Despondency: The Spiritual Teaching of Evagrius of Pontus.