Shingijeon is an invention, because it's the firstself-flying arrow that blows up. The gunpowder strapped behind the arrowhead will explodefew seconds afterit hits a target.A similar weapon was 'invented' in Europe, nearly 300 years later. If you want to see the force of Shingijeon, see the movie 'The Divine Weapon'. I'm a Korean, but this is all I know.(sorry)