“Then, I'll play a soundtrack that matches that, and the writing just happens naturally. It's like I'm not myself almost.”
Kojima explained his relationship between music and writing: half of his work is writing concepts and specifications, and he always does that work with music. When he writes a script he avoids Japanese music because the lyrics intrude on his thoughts, and he also avoids English songs with vocabulary that is too simple; he uses only soundtracks or ambient pieces without vocals. Once the plot and characters are fixed, he plays a soundtrack that fits what he imagines they would say, and the writing simply happens by itself — almost as if it is not him. He then reviews the work once more, this time using the left side of his brain.
“When I'm writing the script though, I don't listen to any Japanese music. With Japanese songs, the lyrics get in the way […] So when I'm writing the script, I listen to either English music or movie soundtracks. […] And then I look it over once more, this time using the left side of my brain.”