How much do you know about magic?

[What's in the box?]

Yeah, I can see a commoner saying something like: "Wizards use fireballs!" and knowing nothing about "Comprehend Languages" but the character in question was a sorcerer, and my thought went along the lines of: "If you use magic every day wouldn't you be aware that there is pretty much a spell for everything? And it is just a matter of finding the right spell?"

It seems like something that should be a part of the Spellcraft skill. Sorta like how 1 rank in Survival means you can always find North. 1 rank in spellcraft should be associated with an approximate knowledge of spells and the existence thereof.