 Within modern occultism and Neopagan religions there are many self-described magicians and witches who practice ritual magical activities.Such people usually define magic as a technique for bringing about changes in the physical world through the force of one's will.The influential British occultist Aleister Crowley (1875-1947) popularised this definition, and religions such as Wicca and LaVeyan Satanism, and magical systems, such as chaos magic have adopted it.