Peaceful Mind in Chinese / Japanese...

安心 can be defined as relief, peace of mind, feeling at ease, to be relieved, to set one's mind at rest, and easiness.

安心 is a nice word that encompasses great meanings within just two characters. Some of the other meanings include pacifying, settling the mind, and peace of mind. It's also the idea of feeling a sense of security, safety, and confidence in your state of well-being.

This can be used by everyone, but some consider it to be a Buddhist concept (You'll find it in your Zen dictionary).

Note: Can be romanized as Anshin or Anjin in Japanese.

靜心 is how to write “peaceful heart” in Chinese.

The first character means peaceful, calm, and quiet. The second means heart but can also mean mind, soul, or spirit.

Because the word for heart/mind/soul is interchangeable in Chinese, this can also be translated as “a peaceful soul” or “a quiet mind.”

I have also seen this translated as “placid temperament” or “spirit of serenity,” especially in Japanese.

While they once used the same first character form in Japan, they now use a slightly-simplified version in modern Japan (after WWII). This version is shown to the right, and can be selected for your wall scroll by clicking on that Kanji instead of the button above.

入靜 is used in Taoism and Qi Gong to describe the state you can reach while sitting quietly in meditation. It contains the idea of achieving a highly-tranquil and peaceful state. Some may describe this state as “sleeping while still awake.”

If you have a relaxation or meditation room, this is the calming wall scroll that you would want hanging in that room.

My Australian friends always say, “No worries, mate.” It's caught on with me, though I drop the “mate” part since it confuses my fellow Americans.

If you would like to express the idea of “no worries,” 放心 is the best and most natural way to say it in Chinese.

The characters you see to the left can be translated as “put your mind at rest” or “to be at ease.” You could literally translate “no worries,” but it doesn't “flow” like this simple Chinese version.

For your info, the first character means to release, to free, to let go, to relax, or to rest. The second character means your heart or your mind.

Note that in Japanese and Korean, this holds the similar meaning of “peace of mind” but can also mean absentmindedness or carelessness, depending on context.

淡泊以明志寧靜而致遠 is a kind of complex ten-character proverb composed by Zhuge Liang about 1800 years ago.

This is a Chinese proverb that means “Leading a simple life will yield a clear mind, and having inner peace will help you see far (into the world).”

What I have translated as “simple life” means NOT being materialistic and NOT competing in the rat race.

The last word means “far” but the deeper meaning is that you will surpass what you can currently see or understand. Perhaps even the idea of opening up vast knowledge and understanding of complex ideas.

The whole phrase has a theme that suggests if you are NOT an aggressive cut-throat person who fights his way to the top no matter how many people he crushes on the way, and instead seek inner peace, you will have a happier existence and be more likely to understand the meaning of life.

See Also:  Serenity

失意泰然 is a very old Japanese proverb that suggests “keeping calm and collected at times of disappointment,” or “maintaining a serene state of mind when faced with adversity.”

It's hard to relate individual character meanings to the overall meaning unless you also understand Japanese grammar. The word order is very different than English. That being said, here's the character meaning breakdown:
失 To miss, lose or fail.
意 Feelings, thoughts, meaning.
泰 Safe, peaceful.
然 Like that, in that way, however, although.

Using these definitions in English, we might say, “Although you may fail or lose, have a feeling of peace and calm.”