Can I use Arcane Eye to cast a Fireball past a solid wall?

Question

One of my players is interested in using Arcane Eye and Fireball in conjunction. From looking at this thread here: Area spells and line of sight, it seems that if a player cannot SEE the target, then the Fireball will explode on whichever obstruction is in its way. However, that's an AND condition, specifically.

So, what happens if a Wizard uses Arcane Eye to peer at the other side of a solid wall. Can they cast Fireball on that spot?

RAW, they can. My original argument was that RAI, it can't, since the Fireball's 'streak of light' hits a solid obstruction and explodes. However, the PHB does explicitly say 'can see' rather than using wording such as having a line of sight or an unobstructed path.

Answer 1

The fireball will explode on the caster's side of the wall

There is no requirement that the caster see the target area (the spell does not specify "that you can see") but there is nothing in the spell that overrides the general rule that there must be a clear path from caster to target.

From the PHB:

A Clear Path to the Target

To target something, you must have a clear path to it, so it can't be behind total cover.

If you place an area of effect at a point that you can't see and an obstruction, such as a wall, is between you and that point, the point of origin comes into being on the near side of that obstruction.

Answer 2

The general rules for targeting are (PHB p. 204):

To target something, you must have a clear path to it, so it can’t be behind total cover.

Fireball does not override those general rules so you must have a clear path between you and the target.

However, there is no general rule that you must be able to see the target and Fireball doesn't not impose a specific requirement so you do not have to be able to see the target!

Answer 3

A bright streak flashes from your pointing finger to a point you choose within range and then blossoms with a low roar into an explosion of flame.

The simple fact that a physical projectile is sent in the direction you point tells me that a wall would certainly stop it. I believe this has been confirmed by Mike Mearls on Twitter as well.

Answer 4

I remember reading a tweet somewhere that LoS is not just being able to see the target, you must have a clear path to it.

Also, one can argue that the fireball doesn't simply explodes on the spot you want to, you throw it from your hands, if there's something like glass on the way the fireball is going to either crack through it or explode on contact, that's up to the DM's discretion I believe, but passing through a solid wall is out of the question.