Not so fast. If I remember correctly, the orcs were created by Sauron when he attempted to make elf-like creatures, but aren't elves turned evil. Infact, as Bilbo portrays them elves are quite fucked up as they are, arrogant and selfish
I'm too tired to dig into it myself, but this person seems to have summed it up:
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"There are a bunch of theories about the true origin of the orcs. Tolkien tried out a few different origins for his Orcs throughout his life but died before he could fully revise The Silmarillion with his final view on their origins and nature.
There is a list of origins proposed by Tolkien(source):
(Continued)"
"-Made of stone and slime through the sorcery of Morgoth;
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-East Elves, where The Silmarillion contains a suggestion that Orcs are descended from East Elves captured by Melkor, their minds and bodies distorted and corrupted.
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-Sentient beasts, another of Tolkien's theories proposes that Orcs may have begun as soulless animals of vaguely humanoid shapes, empowered by the will of the Dark Lord (Morgoth) and learning language only as parrots do.
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(Continued)
"-Fallen Maiar, there are hints in the History of Middle-earth series of books, (especially in Morgoth's Ring in the section "Myths Transformed"), that some Orc leaders, such as the First Age's Boldog, or the Great Goblin encountered by Bilbo and the Dwarves, may in fact have been fallen Maiar which had taken Orc form.
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-Corrupted Men, while Tolkien at some point saw all Orcs as descended from the original corrupted and tortured Elves, later comments of his indicate, according to Christopher Tolkien in Morgoth's Ring "Myths Transformed" text X, that he began to feel uncomfortable with this theory. At about the same time he removed the references to the Thrall-Ñoldorin, he also began searching for a new origin for the Orcs. It seems Tolkien wanted to change the origin of the Orcs to make them corrupted and twisted Humans.
(Continued)
-Some cross-bred with Men, Tolkien also suggested that Men were cross-bred with Orcs under Morgoth's lieutenant, Sauron (and possibly under Morgoth himself). The process was later repeated during the War of the Ring by Saruman. This possibly refers to the way the Uruk-hai and the Half-Orcs were created, in The Lord of the Rings."
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https://scifi.stackexchange.com/questions/26725/what-is-the-true-origin-of-the-orcs
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Either way the consensus is overwhelmingly that they were either made/corrupted by evil, and therefore bent to evil in nature, or else made the decision to be evil
There are several theories on the origin of orcs. The one used in the films was "they were elves once... Taken by the dark powers (morgoth) tortured and mutilated. Now perfected my fighting uruk hai" -Sarumon
'
"There are a bunch of theories about the true origin of the orcs. Tolkien tried out a few different origins for his Orcs throughout his life but died before he could fully revise The Silmarillion with his final view on their origins and nature.
There is a list of origins proposed by Tolkien(source):
(Continued)"
'
-East Elves, where The Silmarillion contains a suggestion that Orcs are descended from East Elves captured by Melkor, their minds and bodies distorted and corrupted.
'
-Sentient beasts, another of Tolkien's theories proposes that Orcs may have begun as soulless animals of vaguely humanoid shapes, empowered by the will of the Dark Lord (Morgoth) and learning language only as parrots do.
'
(Continued)
'
-Corrupted Men, while Tolkien at some point saw all Orcs as descended from the original corrupted and tortured Elves, later comments of his indicate, according to Christopher Tolkien in Morgoth's Ring "Myths Transformed" text X, that he began to feel uncomfortable with this theory. At about the same time he removed the references to the Thrall-Ñoldorin, he also began searching for a new origin for the Orcs. It seems Tolkien wanted to change the origin of the Orcs to make them corrupted and twisted Humans.
(Continued)
'
https://scifi.stackexchange.com/questions/26725/what-is-the-true-origin-of-the-orcs
'
Either way the consensus is overwhelmingly that they were either made/corrupted by evil, and therefore bent to evil in nature, or else made the decision to be evil