Actual evidence that Postive and Negative Energy are opposites?

[Jowgen]

It has occured to me while the words positive and negative are just about the definition of opposites, I can not think of anything in text that actually specifies or proves that these Energy types are somehow invariably opposed to one another.

We know Positive Energy heals living things and damages undead, while Negative Energy heals undead and damages the living; but that is about it. Just because certain creatures happen to react in opposite ways to these energy types doesn't mean the energies themselves are opposites. If these two types of energy were truly antithetic to another, then there should be some evidence of them interacting in certain ways, e.g. directly cancel each other out (like is detailed with numerous Fire and Cold energy type effects).

So, does anybody know of any text examples of PE and NE directly negating or conflicting with eachother? I thought the Postive Energy Protection spell fit the bill, but it just "uses negative energy to offset the effects of positive energy" (i.e. the arguably incidental undead-damaging effect of PE), rather than negating the PE itself. So, it still hold sthe possibility that those two types of energy can happily coexisist in the same space.

Part of the reason I'm wondering this has to do with my favorite substance Voidstone. I thought it would be a funny way to kill something by subjecting it both to voidstone and a major positive dominant environment at the same time, requiring both the save against annihilation and PE-exploding simultaneously. The Voidstone "melting" because of the PE would put a dent in this, so I'm looking to see how clear the RAW and fluff are on the topic.

[WhamBamSam]

There are the energon outsiders native to the Energy Planes, the Xag-Ya and Xeg-Yi, which do an 'opposites attract/matter-antimatter' thing when they get within sight of one another.
If a xag-ya and xeg-yi see each other, they rush together as fast as they can. When they make contact, both creatures are destroyed in an explosion that deals 2d8+18 points of damage within a 3o-foot radius (Fortitude save DC 16 half).

Not exactly hard evidence, but it's a more direct implication given your framing of the issue.

[ZamielVanWeber]

Aoa are a unique form of life that only occur when strongly aligned positive and negative energy collide.

[zergling.exe]

There is a major misunderstanding in what you have said:
We know Positive Energy heals living things and damages undead, while Negative Energy heals undead and damages the living

This isn't entirely true. Positive energy can heal undead just like living creatures. The cure line of spells specifically harms undead, and a number of other positive energy effects do as well, but positive energy itself does not universally harm undead; see the positive energy aligned planar trait for an example.

Negative energy is more universally damage to living creatures however, though undead are not healed by all negative energy effects.

[Zanos]

I think there's at least one spell that deals positive energy damage to living creatures as well.

[GilesTheCleric]

I think there's at least one spell that deals positive energy damage to living creatures as well.

You might be thinking of Boccob's Rolling Cloud (Drag338 49), which deals 1/4 each of elec, fire, negative, and positive damage. All of the damage is damaging, regardless of what creature you use it on. It's a pretty good spell, all-in-all.

[ShurikVch]

I think there's at least one spell that deals positive energy damage to living creatures as well.Not exactly a spell, but Celestial Conduit psionic power (Complete Psionic) do it

[adonis53]

You might be thinking of Boccob's Rolling Cloud (Drag338 49), which deals 1/4 each of elec, fire, negative, and positive damage. All of the damage is damaging, regardless of what creature you use it on. It's a pretty good spell, all-in-all.

Where does it say that it damages regardless? I can't find it and I don't have that exact mag to look at the source.

In libris mortis it specifically states that undead are healed by negative and damaged by positive and living are reversed.

If a specific power/spell/SLA/etc. Says otherwise I'd be interested...

[GilesTheCleric]

Where does it say that it damages regardless? I can't find it and I don't have that exact mag to look at the source.

In libris mortis it specifically states that undead are healed by negative and damaged by positive and living are reversed.

If a specific power/spell/SLA/etc. Says otherwise I'd be interested...


Unlike the negative energy from an inflict wounds spell, this spell does not cure undead (nor does its positive energy component cure living creatures).

However,


negative energy: A black, crackling energy that originates on the Negative Material Plane. In general, negative energy heals undead creatures and hurts the living.

positive energy: A white, luminous energy that originates on the Positive Material Plane. In general, positive energy heals the living and hurts undead creatures.

And again however:


Undead Type: Cannot heal damage on its own if it has no Intelligence score, although it can be healed. Negative energy (such as an inflict spell) can heal undead creatures. The fast healing special quality works regardless of the creature’s Intelligence score.

The PHB's ambivalence on whether these types of damage do or do not always work is probably to account for specific rules where they do not, eg. the Ravid's positive energy lash doesn't heal the living, though it does hurt the dead. If you could quote the LM/ provide a pagenumber (or other references you've found), I'd appreciate it ^^.

[Necroticplague]

Well, there is the cosmological consideration. NEP and PEP are opposite to each other in the same way Fire and Water are: they're on apposite sides of each other, relative to the PMP. Both of them are Inner Planes, along with the four elemental planes. All of them are paired with an opposite in a d6-like arrangement (with the quasielemental and paraelemental planes being the edges of the dice).

[Mordaedil]

There's a cool set-piece in a small adventure based on rebuilding your character in PHBII that concerns this, if I recall correctly. It's called the Cradle of life or something and it has an abyss leading into the negative energy plane and a small island that is part of the positive energy plane and landing on this island admist the darkness was what allowed a person to essentially remake themselves.

The cost is surviving the assault of negative and positive energies in such close proximity.

[Jowgen]

Thank you everyone, this has been quite fascinating.

The Xag-Ya and Xeg-Yi, essentially PE and NE elementals, that can't help but collide and annihilate another in an explosion. Their balanced counterpart the Aoa, resuting from friction of the planes themselves. Lastly, the Necrotic Cradle rebuild location from PHB 2, which illustrates an interesting attraction/repulsion interaction of the PEP and NEP in close proximity to another (which pisses off the Inevitables).

I think this is quite sufficient evidence to pseudo-science/magic characterize the PE and NE relationship.