In the book 1984, who wrote the song that the proles sing?

It looks like George Orwell wrote those lyrics.

http://www.orwelltoday.com/readerprolesong.shtml

In the book "1984" by George Orwell, the song that the proles sing is called "It was only a hopeless fancy." It is mentioned in Chapter 10 of the novel. To find the answer to your question, you can simply read the book and refer to this specific chapter. Reading the book not only provides the answer to your question but also allows you to understand the context and significance of the song within the story of "1984".