Luminous beings are we, not this crude matter

So, perhaps you've heard of me, the breath in everything,
People think I'm energy, though life is what I bring.

I typically come in two varieties, one dark, one light,
Recalled differently in some societies, seeking insight.

I'm used by people of all sorts, healers and fighters,
To bring you balance, I exhort, used by some writers.

Since I'm getting so many answers, I'm adding a hint to narrow things down

Hint:

It's an actual concept/thing/idea and very well known to certain civilizations.

Could you be

Qi (Ch'i)

So, perhaps you've heard of me, the breath in everything,

Believed to be the vital force of all living things. Can translate to "air"

People think I'm energy, though life is what I bring.

Can translate into "life force"

I typically come in two varieties, one dark, one light,

Yin (dark) and yang (light). (From Joe's comment)

Recalled differently in some societies, seeking insight.

Has different characters in different socities https://en.wikipedia.org/wiki/Qi#Characters

I'm used by people of all sorts, healers and fighters,

You can heal with qi and is also a concept in Japanese, Korean, and Chinese martial arts.

To bring you balance, I exhort, used by some writers.

Qìgōng involves coordinated breathing, movement, and awareness. It is traditionally viewed as a practice to cultivate and balance qi.

Acrostic

The acrostic is SPIRIT. Qi is a polysemous word that could also mean spirit.

Title: Luminous beings are we, not this crude matter

Confirmed in another answer that this is part of a quote by Yoda. Yoda is a practitioner of the Force. Qi is a vital "force" for all living things, similar to the Force in the Star Wars universe.

• This is correct. Can you tie the other hints to the answer (the title and the acrostic)? Jul 20, 2018 at 19:45
• The dark and light is referring to rot13(lva naq lnat puv raretl) Jul 20, 2018 at 19:46
• The recall line you got correctly by the way. Jul 20, 2018 at 20:00
• Took a stab at the title and acrostic Jul 20, 2018 at 20:51
• Both of those are what I had in mind for the puzzle. Jul 20, 2018 at 21:38

Are you:

The Force in the Star Wars franchise?

So, perhaps you've heard of me, the breath in everything,

"Life force" can describe the breath, or life in living things.

People think I'm energy, though life is what I bring.

In the Star Wars movies I believe "the force" is described as an "energy" that binds all living things.

I typically come in two varieties, one dark, one light

The Force has two sides, the dark side, and the light.

Recalled differently in some societies, seeking insight.

I'm used by people of all sorts, healers and fighters

In Star Wars the force is used by the Jedi to fight but also for benevolent means.

To bring you balance, I exhort, used by some writers.

A major theme of the Star Wars movies is a restoration of "balance" to the force.

And the puzzle title..

I believe this is a quote from Yoda.

• No, but that's not a bad guess. I would have included the trivia tag if that were the case. Jul 20, 2018 at 15:01
• @Joe-You-Know Is the actual answer better than this one in any way other than that it's the one you're thinking of? Because, especially given the title, this seems like a pretty much perfect fit. (I'm hoping the answer is that yes, the intended answer is clearly better, and the fact that the question looks like it's about The Force is just a witty bit of misdirection.) Jul 20, 2018 at 17:20
• @Gareth McCaughan. Yes, the answer is a much fit than this one. You could say that the Force is a hint to what the answer is supposed to be. It's non-fictional. Jul 20, 2018 at 19:19
• OK! I look forward to learning the intended answer. (Or, I guess, figuring it out myself. But I haven't yet.) Jul 21, 2018 at 0:08

I guess it is / they are ( partial answer)

Carbon element

For,

So, perhaps you've heard of me, the breath in everything, People think I'm energy, though life is what I bring.

Breath consists two parts- inhale and exhale. The later contains Carbon ( of Carbon dioxide). C is the part many hydrocarbons, which are powerhouses. Earth's life is attributed to presence of Carbon( not entirely, though)

I typically come in two varieties, one dark, one light, Recalled differently in some societies, seeking insight.

Coal and Diamond and people comment on the internal structure of these which makes them how they appear.

I'm used by people of all sorts, healers and fighters, To bring you balance, I exhort, used by some writers.

Carbon based healers are possible (?!), there are numerous Carbon based products that we use in our daily life and not sure on the last part, though.

• I'm getting so many interesting answers. This is not what I'm looking for. It may be helpful to think what the title has to do with the puzzle. Astralbee was right in saying that it was a quote from Yoda. Jul 20, 2018 at 17:41

Are you by any chance....

Spirit

Taking the first letter of each line but can also mean either a ghost or a sense of life and also a substance.

So, perhaps you've heard of me, the breath in everything, People think I'm energy, though life is what I bring.

A person can be spirited, and sometimes spirit is used to signify someones soul

I'm used by people of all sorts, healers and fighters, To bring you balance, I exhort, used by some writers.

A fighter has it(heart), healers sometimes use them(alcohol).

• No, but that's not a bad guess. Quantum Twinkie had this answer up earlier, he must have deleted it already. If you expand your reasoning, I'll give you an upvote. Jul 20, 2018 at 15:31
• I amended my answer Jul 20, 2018 at 15:43
• I gave you an upvote. Nice edit. Jul 20, 2018 at 15:46
• this one has me super curious now :D Jul 20, 2018 at 16:02

You are:

Magic

So, perhaps you've heard of me, the breath in everything,


Magic surrounds us and empowers us.

People think I'm energy, though life is what I bring.


Magic is sometimes considered a form of energy (e.g. as "mana" in some role playing games), and, through magic, people can be healed.

I typically come in two varieties, one dark, one light,


Dark (or "black") magic vs. light magic

Recalled differently in some societies, seeking insight.


The exact parameters of magic vary from society to society, for example Indo-European Witchcraft versus Babylonian Astrology. Fortune-telling is a form of magic used for gaining "insight" into the world and the future.

I'm used by people of all sorts, healers and fighters,


In roleplaying games such as Dungeons and Dragons, both the Cleric (a healing class) and several fighting classes are considered "Spellcasters".

To bring you balance, I exhort, used by some writers.


Magic is a common plot element in many stories, such as those of J. R. R. Tolkien and J. K. Rowling.

As to the hint:

Magic is a real phenomenon in academia. Famously, Isaac Bonewits was awarded an interdisciplinary bachelor's degree on the topic of Magic as understood in various fields.

Perhaps you are:

Matter?

So, perhaps you've heard of me, the breath in everything,

Everything living is composed of physical matter. Even the air we breathe is comprised of atoms.

People think I'm energy, though life is what I bring.

Energy and matter are related - it is understood that energy gave rise to matter at the creation of the universe; likewise all atoms contain energy which can be released.

I typically come in two varieties, one dark, one light

Science has only recently discovered the existence of dark matter.

• This is a really good answer. I like it a lot because it fits really nicely. But it's not the answer I'm looking for. Your first guess was closer. Jul 20, 2018 at 15:11

Is it:

Religion?

So, perhaps you've heard of me, the breath in everything,

Religion is a bit of a big deal.

People think I'm energy, though life is what I bring.

Self explanatory.

I typically come in two varieties, one dark, one light,

"light" religions of peace/love/angels and all that, and satanists/cultists

Recalled differently in some societies, seeking insight.

Different religions have different origin stories of life and the universe, which they "recall" differently in order to inform their understanding of the world.

I'm used by people of all sorts, healers and fighters,

Spirit healers, warriors fighting for their God/glory/country, etc.

To bring you balance, I exhort, used by some writers.

God, are you there? It's me, Margaret. Etc.