As the Diamond Age dawned, feeding high-quality sensory input directly to the brain was already easy and common. However, such input had to be prepared beforehand, as modifying a realistic environment on the fly was impossible even for the brightest Artificial Intelligences. This problem was solved near the end of the 22nd century: a completely new design of enviromental patterns was introduced, allowing even a normal, suficiently trained person to alter their virtual surroundings to their heart's content without sacrificing immersion. Although this system (called Fantasion at first) was proposed for use in entertainment and education, its most prominent application turned out to be in the mystical department, as many religious and "philosophic" groups used it for rituals and propaganda.