First impressions matter, but they can be deceiving. We are quick to make opinions about people, and then with time the pretenses fall, and a different persona is revealed. You must have definitely encountered at least one person in your life who appears extremely reserved and quiet initially. Then, one fine day after finally interacting with him/her, you realize how knowledgeable and intelligent he/she is. Calm and unassuming individuals tend to have a treasure of talent and passion in them, while noisy and bubbly ones may be absolutely empty. That's what the phrase 'still waters run deep' means. In conclusion, it simply means there's always more than what meets the eye. Let's know more about the origin and meaning of the proverb still waters run deep with a few examples. The Latin proverb is altissima quaeque flumina minimo sono labi. The literal translation of the phrase is the deepest rivers flow with the least sound. Calm waters are deep, while it is along the bank that the river makes the most noise. This proverb has a very simple and straightforward explanation, wherein, a person who's unassuming or flaccid may have more to his persona than what comes across initially. It is so obvious isn't it, when you are a solid and self-assured, you don't have to do anything to get noticed; your talent and actions will speak for itself. In case of most phrases and proverbs, it's the context of the utterance that determines the exact meaning. Similarly, this proverb can have both negative and positive connotations. A calm and poised person has a deep personality, whereas a seemingly competent person may not be as good as he seems. It can also be used when a seemingly innocuous person behaves in an unexpected way. This proverb can be used in other contexts as well. A person who has faced a personal tragedy, may appear to be cool and composed, but there's a storm of emotions raging beneath the surface. It just goes on to reflect the strength of character of that person and his fierce control over emotions. A learned man will always remain calm, even in the wake of some criticism. That is because his knowledge and experience is deep, and he does not need praise or appreciation to feel good. But, a person who has just started out will react strongly to criticism, and start doubting himself. Another interesting take on this proverb is that a quiet person is the most dangerous one. Talkative people spit out whatever is there in their hearts, but it is the silent ones who'll keep quiet and may hold grudges. The line given below, from William Shakespeare's play Julius Caesar, goes on to show this meaning. Deep people are usually thoughtful, and you can never really predict what's going on in their heads. Much is not known about the origin of this proverb. It was first mentioned in 1400, in Cato's Morals (Cursor Mundi), a Latin collection of proverbial wisdom. It was also included in James Kelly's collection of Scottish proverbs in 1721. By the 19th century, this proverb became very popular and was used on a large-scale. The essence of this proverb lies in the fact that we tend to get carried away with physical appearances, and should try to dig a little deeper. More often than not introverts are considered as boring in this increasingly superficial world. This proverb is a reminder that we must take efforts to get to know someone before intsant judgment.