Knowledge (the Planes)

[Dandu]

Can anyone give me a good reason why Knowledge (the Planes) applies to every plane ever, even the ones an individual has never personally been to?

 

[RUMBLETiGER]

Can anyone give me a good reason why Knowledge (the Planes) applies to every plane ever, even the ones an individual has never personally been to?

Because Knowledge (Local) does that for every place you show up to, even if you've never been there before, and we must maintain consistency.

 

[Sekhmet]

Doesn't apply to demiplanes or planar seeds. >.>
I think it assumes second hand knowledge instead of first hand. I think most people assume Knowledge is what you've picked up over your travels or have heard in passing, but the RAW description is that it represents an academic or scientific body of study.
You read a lot of books, possibly interviewed some experts, and learned about different planes.

(Or live on Sigil)

 

[Morrus]

Can anyone give me a good reason why Knowledge (the Planes) applies to every plane ever, even the ones an individual has never personally been to?

Think of it like the fantasy equivalent of astronomy. Astronomy applies to planets, stars, and galaxies that scientists have never been to. Knowledge (The Planes) applies to planes that adventurers have never been to. They read books, do research, talk to other planar afficionados. maybe even take a PHD or two.

 

[RUMBLETiGER]

I learned about The Infernal Battlefield of Acheron while on the Plane of Air. True Story. (not a true story)

 

[was]

Because listing a knowledge skill for every single plane would be too much.
Because you can research a plane without having gone there.
Because rare knowledge is offset by the DM assigning a high DC.

 

[Empath Negative]

Because a wide variety of planes share similar characteristics, creatures, and laws.

There are an infinite numbers of abyssal layers... but virtually (if not all) of them house demons. All of them have the evil trait, etc etc.

So although you may not know every single plane in existence, you can infer some information and apply that broadly.

 

[Li Shenron]

Can anyone give me a good reason why Knowledge (the Planes) applies to every plane ever, even the ones an individual has never personally been to?

It applies only if you want to...

In a fairly normal campaign, you're probably going to visit 2-3 planes at most during the course of 20 levels. It makes sense then to have one Knowledge(The Planes) to represent scattered knowledge that a character (typically a Wizard) have from reading books on the subject.

In a planar-heavy campaign setting such as Planescape I think it doesn't make sense to have one skill for all planes, but instead split it up in smaller skills such as one per plane.