Written in Los Angeles in 1955, the song “Memories Are Made of This” became a number-one hit for Dean Martin. It was a surprise success in Europe, spending four weeks at the top of the UK Singles Chart. A German version, performed by Freddy Quinn and recast as “Heimweh” (“Homesickness”), was the most popular German song of 1956. As “Honvágy-dal” (“The Song of Homesickness”) it became the anthem of the 1956 Hungarian Revolution.

“Animals retain the memory of their experiences and have no need of mnemonic systems,” according to the third-century Roman writer Aelian. “A horse, on hearing the clash of curb chain and the clang of bit, and seeing chest plates and frontlets, begins to snort and makes his hoofs ring as he prances, and is in an ecstasy.”

The first written language, Sumerian cuneiform, is believed to date to around 3000 bc. Archaeologists have found evidence that astronomical texts were still being written in cuneiform in the first century of the Common Era; decadent varieties of the language survived to the time of Christ.

Researchers at the MIT Media Lab recently determined that all cultural products “follow a universal decay function.” People and things are kept alive through “oral communication” for about five to thirty years. “Biographies remain in our communicative memory the longest (twenty to thirty years),” according to their report, “and music the shortest (5.6 years).”