When I started playing D&D5 I had difficulties understanding the different magical archetypes of the game. Probably because I played a little D&D3 and 3.5 a few years ago and it muddied the water. Now that I am used to it it’s not that complicated by I find that formalizing stuff usually helps me so here we go!
Vancian Magic: a Bad History
A long time ago there was Vancian magic, it comes from some writer named Vance I think. Vancian spells are alive in the mind of the caster, they have to prepare each spell when they wake up. I read somewhere that the read the whole incatation except the last few words, the spell is almost finished, it’s just waiting for the last words to be released! These last words are the magical words that trigged the spell in battle (think “abrakadabra”). This vancian magic was used in older edition of D&D but it’s not anymore because it wasn’t flexible at all. You prepared exactly the spell you were going to cast so if you had 3 first level slots and 2 second level slot you may have prepared:
- 2 command spells
- 1 bless spell
- 1 spiritual weapon spell
- 1 lesser restoration spell
During the day if you realized that you didn’t need your spiritual weapon and would like to replace it with lesser restoration it wasn’t possible. I think they were some exception, like the Cleric was able to replace any vancianly prepared spell with a heal spell but the flexibility was very low.
In D&D5 they replace this with pseudo-vancian magic. The idea is that you have a pool of spell that you can pick from when you use a spell slot to cast a spell. The flexibility of this pool depend on your class.
Some classes learn new spells after certain events (usually when they level up) and their pool contains all the spell they know so they don’t need to prepare spells (alternatively you could say that they have all of their spells prepared all the time). The Bard, Sorcerer, Ranger, Rogue Arcane Trickster, Warlock works like this. They all have a “known spell” column in their table in the books. I call them school-of-life magicians.
Some classes know all of their spell from the start and their pool contains a subset of their choice that they can change after every long rest, that’s when they prepare their spells. The Cleric, Druid and Paladin work like this. I call them know-it-all magicians.
You will notice that Wizards are not mentionned, that’s because they are a weird case.
The case of the Wizard
The Wizard is a weird case. They learn new spell when they level up but also when they find scroll or spellbooks.
You might find other spells during your adventures. You could discover a spell recorded on a scroll in an evil wizard’s chest, for example, or in a dusty tome in an ancient library
Technically there is no “known spell” column in the PHB table but the text says (page 114):
At 1st level, you have a spellbook containing six 1st-level wizard spells of your choice.
Each time you gain a wizard level, you can add two wizard spells of your choice to your spellbook.
That means that even if wizards don’t automatically know all of their spell, they could learn a lot of them (and it’s the class that has access to the most spells) so for balance reason they can’t have “all of their spells prepared all the time”. That’s why they have to prepare a subset of their spells after every long rest.
In conclusion Wizard are hybrids. I call them learn-it-all.