I Make Myself Invisible in Articles by Aleister Crowley.

“The forces had other and worse effects. An employee (who had not touched alcohol for twenty years) suddenly got drunk and tried to murder his wife and children. This was one of many similar cases.

One summer more than half my pack of bloodhounds died. My servants were always getting ill.

One of the men I employed to lay down putting greens went insane and tried to murder my wife.” [via, also]

Consider also:

  1. “Then the fun began. We saw–and my teacher was able to identify–hundreds of shapes, weird “half-formed faces” which were thronging the room, marching in fantastic dance about its confines. These were definitely malicious forces, demons, which one had to study and conquer.”
  2. “One night, after a ceremony in which a well-known analytical chemist was my leader, I locked the door and went out with him to a meal. When we returned the door was wide open, though the lock had not been forced, and the whole contents of the temple had been thrown about and lay in the wildest confusion.”
  3. “now he wrote, ‘O glory, and O delight! I have entirely reduced that spectrous fiend to his station’–he had overcome the merely reasoning and sensual portion of the mind–‘whose annoyance has been the ruin of my labours for the last twenty years of my life….”
  4. “I always think of Mr Wells’ First Men in the Moon. How to act when the fundamental conditions of life are changed? The danger of making fatal mistakes is always present.”
  5. “A necessary part of the practice of magic is the invocation of Divine and angelic beings and the evocation of blind forces, some of which are considered ‘evil’ by the vulgar.”