Consider a first-order logical knowledge base that describes worlds containing people, songs, albums (e.g., “Meet the Beatles”) and disks (i.e., particular physical instances of CDs). The vocabulary contains the following symbols:
${CopyOf}(d,a)$: Predicate. Disk $d$ is a copy of album $a$.
${Owns}(p,d)$: Predicate. Person $p$ owns disk $d$.
${Sings}(p,s,a)$: Album $a$ includes a recording of song $s$ sung by person $p$.
${Wrote}(p,s)$: Person $p$ wrote song $s$.
${McCartney}$, ${Gershwin}$, ${BHoliday}$, ${Joe}$, ${EleanorRigby}$, ${TheManILove}$, ${Revolver}$: Constants with the obvious meanings.
Express the following statements in first-order logic:
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Gershwin wrote “The Man I Love.”
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Gershwin did not write “Eleanor Rigby.”
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Either Gershwin or McCartney wrote “The Man I Love.”
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Joe has written at least one song.
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Joe owns a copy of Revolver.
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Every song that McCartney sings on Revolver was written by McCartney.
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Gershwin did not write any of the songs on Revolver.
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Every song that Gershwin wrote has been recorded on some album. (Possibly different songs are recorded on different albums.)
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There is a single album that contains every song that Joe has written.
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Joe owns a copy of an album that has Billie Holiday singing “The Man I Love.”
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Joe owns a copy of every album that has a song sung by McCartney. (Of course, each different album is instantiated in a different physical CD.)
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Joe owns a copy of every album on which all the songs are sung by Billie Holiday.