To Be Like Water in Chinese / Japanese...

上善若水 is a quote that is sometimes presented as “Be like water.”

However, this is an ancient quote from the great philosopher Lao Tzu. It suggests that the ultimate goodness and purity (in the world) is water. Many take this as a suggestion to be like pure/good water.

若水 is part of a very old saying from Lao Tzu.

In these two characters, there is a suggestion to be like water. The full phrase is about the goodness and purity of water. So, when this suggests being like water, it is actually a suggestion to be a good person (one who does not dishonor himself/herself, etc.).

像水一樣 is a short quote from a much longer statement by Bruce Lee.

He summarized how people should be flexible to all circumstances, attacks, or situations. In the end, he exclaims, “Be like water, my friend.” 像水一樣 is the “Be like water” part alone since that seems to be what most people want.

水の心 is the Japanese Buddhist and martial arts phrase, “Mizu no Kokoro,” which means “mind like water” or “heart of water.”

The phrase is a metaphor describing the pond that clearly reflects its surroundings when calm but whose images are obscured once a pebble is dropped into its waters.

鏡花水月 is an old Asian proverb that means “flowers in a mirror and the moon reflected in the lake” or “flowers reflected on a mirror and the moon reflected on the water's surface.”

Literally, 鏡花水月 reads “Mirror Flower, Water Moon.”

Figuratively this can be used to represent a lot of different ideas. It can be used to express an unrealistic rosy view or viewing things through rose-tinted spectacles. So you can use it to relay an idea about something that is visible but has no substance, something that can be seen but not touched, or something beautiful but unattainable such as dreams or a mirage.

This expression is used to describe things like the subtle and profound beauty of poems that cannot be described in words.

鏡 = Mirror (or lens)
花 = Flower(s)
水 = Water
月 = Moon

Can also be written 水月鏡花 (just a slight change in word/character order).

清 is a word that means clarity or clear in Chinese, Japanese Kanji, and old Korean Hanja.

Looking at the parts of this character, you have three splashes of water on the left, “life” on the top right, and the moon on the lower right.

Because of something Confucius said about 2500 years ago, you can imagine that this character means “live life with clarity like bright moonlight piercing pure water.” The Confucian idea is something like “Keep clear what is pure in yourself, and let your pure nature show through.” Kind of like saying, “Don't pollute your mind or body, so that they remain clear.”

This might be stretching the definition of this single Chinese character but the elements are there, and “clarity” is a powerful idea.

Korean note: Korean pronunciation is given above but this character is written with a slight difference in the "moon radical" in Korean. However, anyone who can read Korean Hanja, will understand this character with no problem (this is considered an alternate form in Korean). If you want the more standard Korean Hanja form (which is an alternate form in Chinese), just let me know.

Japanese note: When reading in Japanese, this Kanji has additional meanings of pure, purify, or cleanse (sometimes to remove demons or "exorcise"). Used more in compound words in Japanese than as a stand-alone Kanji.

湖 means lake in Chinese, Japanese Kanji, and old Korean Hanja.

湖 is used in place names (like Lake Huron) and as a descriptive term for any large body of fresh water.

In Japanese, this can also be the female given name Reiku.

If your surname is Lake, this could be a good character for you.

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.

In Japanese, 無心 means innocent or without knowledge of good and evil. It literally means “without mind.”

無心 is one of the five spirits of the warrior (budo) and is often used as a Japanese martial arts tenet. Under that context, places such as the Budo Dojo define it this way: “No mind, a mind without ego. A mind like a mirror which reflects and dos not judge.” The original term was “mushin no shin,” meaning “mind of no mind.” It is a state of mind without fear, anger, or anxiety. Mushin is often described by the phrase “Mizu no Kokoro,” which means “mind like water.” The phrase is a metaphor describing the pond that clearly reflects its surroundings when calm but whose images are obscured once a pebble is dropped into its waters.

This has a good meaning in conjunction with Chan / Zen Buddhism in Japan. However, out of that context, it means mindlessness or absent-mindedness. To non-Buddhists in China, this is associated with doing something without thinking.
In Korean, this usually means indifference.

Use caution and know your audience before ordering this selection.

More info: Wikipedia: Mushin