Is The trope that wizards can't use armor just an arbitrary limitation?

[Anthony]

Originally Posted by sir_pudding

Neither Merlin nor Gandalf are typically depicted as heavily armored.

Heavy armor was largely absent in LoTR, and Merlin was, well, a royal adviser, not a soldier.

[sir_pudding]

Originally Posted by Anthony

Heavy armor was largely absent in LoTR, and Merlin was, well, a royal adviser, not a soldier.

Sure, but there's hardly any examples of spell-casting fantasy wizards prior to D&D at all. Prospero and the Weird Ladies also don't wear any armor.

[whswhs]

Originally Posted by sir_pudding

Sure, but there's hardly any examples of spell-casting fantasy wizards prior to D&D at all. Prospero and the Weird Ladies also don't wear any armor.

Elric of Melniboné. Sheelba of the Seven Eyes and Ningauble of the Eyeless Face.

Bill Stoddard

[sir_pudding]

Originally Posted by whswhs

Elric of Melniboné.

Which is clearly one of the inspirations for Pathfinder's Magus class. I'm just saying there's obviously a source for the robes and pointy hat wizard that predates D&D.

[Agemegos]

Originally Posted by sir_pudding

Which is clearly one of the inspirations for Pathfinder's Magus class. I'm just saying there's obviously a source for the robes and pointy hat wizard that predates D&D.

Yes. Especially with astrological symbols embroidered on the robe it is the get-up of a mediaeval doctor.

Likewise with potions made of weird ingredients, magical incantations in obsolete languages, slips of paper with magical words and diagrams on them worn as amulets, gathering ingredients and making potions at astrologically-defined times and while repeating incantations in obsolete languages, etc.

Medicine has come a long way since Semmelweiss and Lister.

[whswhs]

Originally Posted by sir_pudding

Which is clearly one of the inspirations for Pathfinder's Magus class. I'm just saying there's obviously a source for the robes and pointy hat wizard that predates D&D.

Sure. But there are two different concepts here: The wizard who doesn't go around in armor, and the wizard who is not allowed to wear armor. Or use weapons. Does your mage not pick up that sword because he hasn't been trained to use it, or because it's magically impossible for him to do so, or because his magic will desert him if he messes with weapons? Gandalf, at least, was a pretty impressive swordsman. Or swordsmaia.

Bill Stoddard

[Irish Wolf]

Can't speak to original D&D, but AD&D's first edition specified that metallic armors were incompatible with higher magics. They also claimed that mailed gauntlets would interfere with the subtle gestures needed to case spells.

[The Colonel]

This sort of thing seems to assume a class based RPG - I've only encountered it outside class based games in a context where it appears to be a deliberate attempt to mimic the same effect.
The main reason seems to be either PvP balance or niche protection - explanations given as fluff rarely make any sense.
And of course, there's "that one specific class based RPG" with its origins in wargaming where "magic users" and "fighting men" were simply different kinds of unit with different capabilities, without needing to probe too far into the underlying reality of the thing.
The whole "you can't do it at all because stuff" position is distinctly old school - the modern trend (and the same trend that has always existed in non-class systems) would be towards "you can try, but you'll suck at it" ... which seems far more congruent.

Mythically speaking, wizards tend not to wander about in armour (although sword wielding seems reasonably common), but on the other hand they tend not to shoot fireballs either. Also, most mythic wizards are (or appear to be) very old, which may also impair their fighting ability.

[shawnhcorey]

Originally Posted by Irish Wolf

Can't speak to original D&D, but AD&D's first edition specified that metallic armors were incompatible with higher magics. They also claimed that mailed gauntlets would interfere with the subtle gestures needed to case spells.

Yes, that seems to be derived from folk tales the the magical fair folk, that is, the Fae, cannot abide iron in any form.

[Polydamas]

Originally Posted by whswhs

Elric of Melniboné. Sheelba of the Seven Eyes and Ningauble of the Eyeless Face.

Bill Stoddard

And quite a few Robert E. Howard enemies and third parties. Dr. Karadur of Mulvan was too old and frail for armour, and Harold Shea didn't wear armour either ... but early L. Sprague de Camp seems to have got his fencing from the likes of Egerton Castle rather than Alfred Hutton.