"I Am a Rock" is a song written by Paul Simon. It was first performed by Simon alone as the opening track on his album The Paul Simon Songbook which he originally recorded and released in August 1965, only in the United Kingdom. Paul Simon and Art Garfunkel, as the American folk rock duo Simon and Garfunkel, re-recorded it on December 14, 1965, and included as the final track on their album Sounds of Silence, which they released on January 17, 1966.

The song was not included on Simon & Garfunkel's first album, Wednesday Morning, 3 A.M., which they released on October 19, 1964. The folk-rock nature of the music makes it unlikely that Simon would have written it much earlier than 1964, when he first began experimenting with the folk genre. Some sources say that it was performed by Simon on January 27, 1965, on a promo show for the BBC. In any case, Simon seems to have written the song before the end of January 1965, and certainly had it down before May, when he recorded it. Thematically, the song deals with isolation and emotional detachment.

The original version of "I Am a Rock" was first released on The Paul Simon Songbook, and became, in the summer of 1965, the A-side to Simon's only single released from the album, backed with "Leaves That Are Green" on CBS 201797. Like the album, the single was not a commercial success. It is an extremely rare single to locate. Meanwhile, The Paul Simon Songbook, which for a long time Simon himself had disdained as an album, remained available only in the United Kingdom until 1981.

While Paul Simon was in Europe during the summer of 1965, Tom Wilson, the producer of Wednesday Morning, 3 A.M., responded to requests for "The Sound of Silence" from American radio stations and dubbed an electric guitar and drums onto the original track. He then released the song as a single, whereupon it entered the United States pop charts. When Simon heard about the success of this song, he was still touring in Europe as a poor solo folk singer. He immediately returned to the United States, and in December 1965 he and Garfunkel began a series of hasty recording sessions to match the electric "mold" created by Wilson with many of the other songs that Simon had recorded on the Song Book, including "I Am a Rock," which was re-recorded during these sessions on 14 December 1965. The result was the album Sounds of Silence, which the duo released the following January. "I Am a Rock" was the fifth and closing track on Side 2 of the record. With "The Sound of Silence" (the opening track), it bookends the rest of the material. This album quickly capitalized on the success of the new album's title track as a #1 single, and itself rose to #21 on the Billboard charts.

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