Magic Is Mental

""Don't look at me like I'm going to shoot lightning from my fingers or summon the Devil. Or worse, like I think I can. Magic is a psychological discipline.""

- Alan Crowe, magician, Global Frequency

A trope that is nearly omnipresent when magic is involved: Magic is a product of the mind, not the body. Magic requires study and concentration to use. The best mages are smart, wise, perceptive and are all around great minds. It's even in the word "Wizard" which used to mean "Philosopher" and came from the word "Wise". The word magic itself descends from magos "one of the members of the learned and priestly class". It's not accidental wordplay that forces you to learn basic spelling before you can study spellcasting.

As such, this trope has many, many consequences: In an ensemble group, those with magics will tend to be the smartest. They are the most well-learned, those who have studied and are the wisest. They will be The Smart Guy.

In games with stats, magic is often related to a "mental" attribute if it's not its own, segregated attribute. Popular choices are intelligence/smarts/logic, willpower/wisdom/spirit or charisma/personality. Different types of magic may require different attributes, with Hermetic Magic favoring the first, and divine magic favoring the second.

This trope is why we have Squishy Wizard - magic requires a strong mind, not a strong body, and this is the handwave often used.

Often, Asian works follow the trope less rigorously, with magic being shown as a product of both mind and body. Thus seeing character study, train and combine magic with martial arts is not rare.

Related to Enlightenment Superpowers. See also Ritual Magic which may involve a lot of memorization and concentration. Not to be confused with (but might coexist with) Power Born of Madness.

Comic Books

 * Comic book characters using magic (especially the wizard kind) often are intellectuals. Notably, DC Comics' Doctor Fate and Marvel's Doctor Strange are two spellcasters with the title of "Doctor", which itself implies a level of education (e.g. Doctor Strange was a neurosurgeon and his successor, Doctor Voodoo, was a psychologist).
 * Strange in particular has mentioned that spellcasting requires a strictly disciplined, focused mind. "If you do not pay the utmost attention, magic can get away from you in a heartbeat. Every spell, every sigil, every manipulation... you must keep a close eye on everything so it doesn't backfire."

Literature

 * In Discworld, wizard-magic is based on knowledge (the three known wizarding universities are the Disc's centres of pure learning, compared with the vocational schools run by the guilds), and witch-magic is based on force of personality. (In D&D terms, Intelligence and Charisma.)
 * In The Imager Portfolio by L. E. Modesitt, Imagers use their 'magic' completely with their minds, by seeing/imagining them in their heads, but they have to have a complete mental picture and understanding of it's elemental and chemical make up or they can do things like blow themselves up by mixing chemicals which react explosively with each other. They also can image in their sleep as they dream, so they have to sleep in protected, lead shielded rooms, alone, even if they are married (or they could accidentally kill their spouses).
 * This is how (human) magic works in Rivers of London books. You have to learn the mental forms in order to do magic, and practice visualising the concepts or it doesn't work. To make things harder, thanks to Isaac Newton, all the names of the forms are in Latin. And the forms have to stack in order to work. To throw a fireball, you have to learn how to visualise the fire, then how to visualise the it moving, then have to visualise how to make it track a target... And after that your brain trickles out your ears (if you've done it wrong).
 * In Necroscope in order to gain the power to time travel and teleport Harry Keogh, and his heirs, has first to be able to calculate the Infinite length of a Moebius strip in finite terms. When he is stripped of his ability to do math he loses that ability. He has other innate abilities, and most psi users abilities are inborn, but this one has to be learned and expressed mathematically.
 * The Dresden Files magic stems from life and emotions, but concentration and willpower are what allows one to use magic to achieve anything.

Oral Tradition

 * Most depictions of Merlin fits this. He's a wise advisor, and a powerful wizard.

Tabletop Games

 * In Dungeons and Dragons, wizards used their intelligence as the stat governing their magic. Clerics used wisdom. In later edition, some classes used charisma. Generally, "Learned" arcane magic was tied to intelligence, divine and natural magic to wisdom, and inborn magic to charisma.
 * 4th edition both inverts the trope, and plays it straight. Wizards use intelligence. But classes like the sorcerer and warlock can use physical attributes like constitution and strength to cast magic. Often because the powers they wield are dangerous to themselves, thus they need a fit body to channel them. The Battlemind (a psychic warrior) beats people to death with the power of his physical health (constitution).
 * In Shadowrun, Magic is it's own attribute, but only the mental attributes (Logic, Intuition and Charisma) can be used to resist drain, the strain of using magic. Thus having higher attributes allows one to cast more spells.
 * In most Savage Worlds setting, magic is related to the spirit attribute. If not, it's smarts. But always one of those two.
 * In Magic: The Gathering in-role your cards are your spells, and you draw them from your library. Many cards that affect cards in your hand and library (drawing, discarding, searching, etc.) represent things happening to the mind or knowledge, and a few other cards represent things happening to cards in your graveyard (your discard pile) as affecting memories.
 * In GURPS, "Magery" (the advantage that allows you to be a mage) is a mental advantage, which means that it stems from your mind rather than from your body (so it stays with you if you switch bodies with someone, etc.)

Video Games

 * In Ogre Battle, Intelligence determines a magic attack's damage.
 * In The Elder Scrolls games, Intelligence determines one's mana, thus how many spells they can cast in a short amount of time. Intelligence also governs alot of the magical skills. Those that don't fall under it fall under Willpower or Personality.
 * Willpower is also used to determine how quickly your mana regenerates.
 * In the Ultima games, one's spellcasting depends on either intelligence or wisdom.
 * In the Wizardry series, spellcasters depend on either intelligence, senses or piety.
 * Diablo III uses Wisdom as the attribute governing mana and magic damage.
 * In Warcraft III, intelligence dictates a hero's mana, and magical heroes' damage.
 * In Final Fantasy IV and Final Fantasy XI, intelligence dictates magic damage. In most other games of the series, Magic Power is it's own stat.
 * In Quest for Glory, Intelligence affects your ability to cast spells and your mana if you are a Magic User.
 * In Fable, Magic falls under "Will".
 * In Dragon Age Origins, Willpower determines mana.
 * Interesting subversion in that Cunning—the stat that models the character's raw intellectual capacity, social acumen, cleverness and perceptiveness, does not aid magic in any way.
 * In the Lufia games, Intelligence determines spellcasting power.
 * Games based on or inspired by Dungeons and Dragons do this:
 * Baldur's Gate I and II and Baldur's Gate: Dark Alliance
 * The Neverwinter Nights games
 * Temple of Elemental Evil
 * Golden Sun has this in the form of psynergy, short for psychic energy.
 * Dark Souls has this with standard sorcery, as intelligence raises your ability to use sorcery catalysts and allows you to learn higher level spells.