Divination

Divination (占い) is the process of acquiring insight into questions or situations (such as the foretelling of future events or remote and unseen circumstances), through the use of magic and the occult.

In both real life and the Toaru series, there are many different methods of divination.

Etymology
Divination is derived from the Latin divinare, meaning "to foresee, to be inspired by a god" (related to divinus, divine).

Many terms used to describe variations of divination, which are derived from Ancient Greek compounds, include the suffix μαντεία (manteía), meaning "prophecy or divination." Examples include (divining from the dead),  (divining from cards) and  (divining from books).

Principles
There are many different methods of divination, across a variety of cultures and magical systems.

Astrology is one well-known means of divination, using the objects and phenomena in space, with variations found in different cultures across the world.

Another well-known method is through the of tarot cards, with meanings derived from the arrangements which the cards appear in.

is a method which is used with grimoires and other similar books. The user takes the grimoire, pictures their worries in their head and flips through the book, then they place their finger on a specific passage and read it to find the answer to their problem. There are also texts which are specifically compiled for divination purposes, such as from China.

Other methods include Necromancy (though in more recent times, this particular term also tends to cover manipulation of the dead other than for divination), Kokkuri and Enochian chess.

Lie detectors based on fortune telling are common in the magic world, but they are difficult tricks to actually use as the spells require being in a limited one-on-one space like ordinary fortune telling and require the user to be focusing on a conversation with the target.

Background
One particular case of divination which greatly influenced the events of the Toaru series was that of Allan Bennett, who through the use of tarot cards, foretold the death of Aleister Crowley's future daughter Lilith Crowley through the effects of the 'sparks' from colliding phases, a phenomena which the Golden Dawn was contributing to. On learning this, Aleister would instigate the cabal's destruction and subsequently seek the destruction of the phases and all magic.

Daihasei Festival Arc (Index)
Tsuchimikado Motoharu made use of an Onmyoudou-based Divination Circle in order to track down Oriana Thomson during the events of the Daihaseisai.

Toaru Majutsu to Kagaku no Ensemble
Taking umbrage at Kamijou Touma's attitude towards fortune telling, Sozty Exica proceeded to read his fortune using Navagraha Astrology.

Toaru Majutsu no Index SS: Agnese's Magic Side Work Experience
During the summoning incident, simple map fortune telling was used to narrow down the possible location for the ceremonial ground to a 10km block, with other summoning ceremonies in the area experiencing 'interference'. Agnese Sanctis also made use of a lie detector spell with a pair of scissors, derived from fortune telling methods, while interrogating the five suspects.

Salome Arc
Weather Girls Sunny and Rain were mentioned as fortune tellers, who used fortune telling to gather information for the Kamisato Faction. Using a globe which provides a weather map of the planet and the movement of the stars, their fortune telling was noted to bypass conventional data protection and able to obtain precise information over a wide area.

Aleister Crowley Arc
During the recreation of Aleister Crowley's past, shown to Kamijou Touma in the Windowless Building, the events surrounding Allan Bennett's prophecy concerning Lilith Crowley's fate, derived from tarot-based divination, were shown.

Coronzon Arc
During the events surrounding the Crowley's Hazard invasion of the United Kingdom and the emergence of the recreated Golden Dawn, the method of bibliomancy with grimoires was mentioned, with regards to Aleister Crowley's use of it with the Book of the Law.

During the attack on the Queen Britannia, Mina Mathers considered the use of to determine the correct procedure for reaching the ship's temple, thinking that Coronzon may have taken measures against the use of Tarot for the purpose.

Christmas Eve Arc
Fortune telling was among the services provided by R&C Occultics.