But if the same character insists on telling the truth when a lie would save his life, then we sense that honesty is at the core of his nature. In all other arts the answer is self-evident. The composer has his instrument and the notes it sounds. The dancer calls her body her instrument. Sculptors chisel stone.
Painters stir paint.
The stuff of story is alive but intangible. I hear you thinking. But I have my words. I can put hands on my pages. The writer's raw material is language.