Simplicity in Chinese / Japanese...

簡 expresses the idea of something simple or the essence of simplicity in life in Chinese.

This can also refer to a simple slip of bamboo for taking notes or writing a letter (especially in Korean Hanja).

Technically this is a word meaning simplicity and brevity in Japanese but it's rarely used in modern Japanese. Therefore, you should probably only select this character if your audience is Chinese.

See Also:  Brevity

単純 or Tanjun is a Japanese word that means simplicity, simple, and/or uncomplicated.

Do you want to live the “tanjun lifestyle”? Maybe this wall scroll will remind you to uncomplicate your life.

In Japanese, 質素 means “simplicity,” “modesty,” and/or “frugality.”

While these Japanese Kanji are also currently-used Chinese characters, they do not create a single word or idea in Chinese. Therefore, only select this if your audience is Japanese.

See Also:  Modesty | Prudence

內心平靜 is a Chinese and Japanese phrase that is a direct translation of the western idea of inner peace.

The first two characters contain the idea of “heart,” “innermost being,” or “deep in the/your inner mind.”

The last two characters mean “tranquil” and “serene.”

I have seen this phrase used as “inner peace” for art prints and even on the side of coffee cups. But I think the translation is too literal. It feels like a direct translation from English rather than a nicely composed Chinese or Japanese phrase. See my other entries for “inner peace.”

See Also:  Serenity | Peace

和 is the simplest form of peace and harmony.

和 can also be translated as the peaceful ideas of gentle, mild, kind, and calm. With a more harmonious context, it can be translated as union, together with, on good terms with, or on friendly terms.

Most people would just translate this character as peace and/or harmony. 和 is a very popular character in Asian cultures - you can even call it the “peace symbol” of Asia. In fact, this peace and harmony character was seen repeatedly during the opening ceremony of the 2008 Olympic Games in Beijing (a major theme of the games).

In old Chinese poems and literature, you might see this used as a kind of "and." As in two things summed together. As much as you could say, "the sun and moon," you could say "the sun in harmony with the moon."

See Also:  Inner Peace | Patience

質実剛健 is a Japanese word that can mean “unaffected and sincere, with fortitude and vigor” or “simplicity and fortitude.”

The first two characters, 質実 mean simplicity or the “essence of something.”
The last two, 剛健, mean strength, fortitude, or strong composure.

侘寂 is Wabi-Sabi, the aesthetic sense in Japanese art emphasizing quiet simplicity and subdued refinement.

More about this subject at Wikipedia: Wabi Sabi

幽玄 is the Chinese, Japanese Kanji, and old Korean Hanja word meaning dim, deep, mysterious, subtle grace, hidden beauty, mysterious profundity, elegant simplicity, or subtle and profound.

This can also be the Japanese personal name Yuugen or Yugen.

平常心 is the title Heijoshin, as associated with Kendo and Aikido schools of Japanese martial arts.

平常心 is also a word in Japanese that can be translated as “one's self-possession” or “presence of mind.”

In Chinese and Korean, this means “simplicity heart,” “composure,” “calmness,” or a “sense of orderliness.” In Chinese and Korean, this implies that you enjoy what you have, keep your heart in balance, and have no over-blown ambitions.

寂 means silent, solitary, quiet, calm, still, rest, or tranquil.

This also has a strong association with Buddhism where it can mean “entering into Nirvana.” In that context, this is sometimes used to refer to the passing of a Buddhist monk (he is silent, as he has entered Nirvana). For the living, this is about tranquility (especially of mind).

Some will also use this to mean “elegant simplicity.”

From Sanskrit, this can represent praśama, vivikta, śānti, or nibbāna (nirvāṇa).

真如 comes from the Sanskrit and Pali word often romanized as “tathata” or “tathatā.” Originally written, “तथता.”

It's a Buddhist term often translated as “thusness” or “suchness,” but this does not explain it.
A better explanation may be “the ultimate nature of all things” or “ultimate truth.” However, this gives it too strong of a feeling. This concept is sometimes described as being in awe of the simple nature of something - like a blade of grass blowing in the wind or ripples on water. It is what it is supposed to be, these things follow their nature. Amazing in their mundane simplicity.

Every sect of Buddhism will have a slightly different flavor or explanation, so don't get fixated on one definition.

Notes: Sometimes Buddhists use the word dharmatā, a synonym to tathatā.

In Japan, this can also be the female given name Mayuki, or the surname Majo.