Why did George Lucas start at 4?

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Tags

1. #however
2. #plans
3. #started
4. #because
5. #crawl
6. #prequel
7. #system
8. #strikes
9. #numerical
10. #called
11. #empire
12. #while
13. #renamed
14. #episode
15. #later
16. #lucas
17. #trilogy