Related Clues:

• Creative inspiration
• Crux of the matter
• Main theme
• Hymn part
• Future invention
• What a germ may become
• "Nessun dorma" singer
• It starts in your head
• Invention's origin
• Think about it
• Flash of brilliance, perhaps
• Start of a solution
• Inventor's ''light bulb''
• It might be bright
• Jussi Bjorling, notably