OK, so my roommate and I have a bit of a disagreement when it comes to area spells. Now, I want to say first and foremost, we are not talking about fireball. It seems to be an exception to the rule. But here is the section I am referencing.
Area: Some spells affect an area. Sometimes a spell description specifies a specially defined area, but usually an area falls into one of the categories defined below.
Regardless of the shape of the area, you select the point where the spell originates, but otherwise you don't control which creatures or objects the spell affects. The point of origin of a spell is always a grid intersection.
I omitted the rules about what creatures are effected, because our issue is with the targeted area. Now it says that "The point of origin of a spell is always a grid intersection." The crux of the matter is, do you need line of sight or just line of effect to target that grid intersection. Here is an example spell.
SOUND BURST
School evocation [sonic]; Level bard 2, cleric 2
Casting Time 1 standard action
Components V, S, F/DF (a musical instrument)
Range close (25 ft. + 5 ft./2 levels)
Area 10-ft.-radius spread
Duration instantaneous
Saving Throw Fortitude partial; Spell Resistance yes
You blast an area with a tremendous cacophony. Every creature in the area takes 1d8 points of sonic damage and must succeed on a Fortitude save to avoid being stunned for 1 round. Creatures that cannot hear are not stunned but are still damaged.
The reason is for situations like being in total 100% darkness and cant see, or being blind. Any help here would be appreciated, also, any links to Paizo staff regarding said topic would be amazing too. Thanks for the help in advance!
If the target was a creature, you would need line of sight. But since the target of the spell is an area you only need line of effect. There is nothing preventing a caster from throwing out AoE spells when they are blinded or otherwise unable to see where they want to hit, as long as it's not physically (or magically) blocked.