Worth one s salt

Doctors always advise us to take less salt if we want to have a healthy lifestyle. In the following sentence, what is the manager’s opinion of the new worker? 

The manager thinks that the new worker is worth his salt. 

The manager actually thinks that the new worker is good at his job. You might have thought the opposite because salt is cheap and may lead to health problems, including high blood pressure. 

Why does the idiom “worth one’s salt” mean “competent and worth one’s salary”? Salt was valuable in the past, and was sometimes called “white gold”. Some countries even fought over salt in ancient times. It has been used as food seasoning and meat preservative for thousands of years. 

Historians think that there is a link between salary and salt. During the Roman Empire（羅馬帝國）, soldiers received salt as part of their pay or some special money（or “salarium”） to buy their own salt. The English word “salary” comes from the Latin “salarium”. Latin（拉丁文） was spoken throughout the Roman Empire. A lot of English words come from Latin. 

The idiom “worth one’s salt” was used as early as 1805 when Philip Beaver, an officer of the British Royal Navy（英國皇家海軍）, wrote in a report of an expedition entitled “The African Memoranda” （《非洲摘記》）: 

“Hayles has been my most useful man, but of late not worth his salt.” 

In 1830, Robert Louis Stevenson, a famous Scottish （蘇格蘭）author, also used this idiom in his classic adventure novel, “Treasure Island”（《金銀島》）: 

“… our new hand was worth his salt.”（我們的新工人工作稱職。） 

The expression also means that “someone deserves respect”, as Theodore Roosevelt, the 26th President of the United States（美國總統）, said in early 20th century: 

“No man is worth his salt（應受尊敬）who is not ready at all times to risk his well-being, to risk his body, to risk his life, in a great cause.” 

Let us remember that no one is worthless if he or she is worth his or her salt.