Film is the most popular art form today because it is the art form that most resembles real life. In the future, that medium may become virtual reality (VR) and ultimately full-world simulations. But for now, movies are the most visceral medium because they look and sound like real life.

I don’t understand how anyone can claim a certain book is unfilmable, unless that reason is budgetary. However, many people say a book is unfilmable in regards to its narrative style. But I think they’re wrong.

Any book is filmable, even if it takes place entirely in someone’s head. You can use voiceover to convey their thoughts. And if you say, well then that would be boring. Why? Was the book boring? No. Then why would it be boring on screen? Either the voiceover is captivating in itself, regardless of the visuals, or it’s not. Theoretically, you could make a compelling film entirely of one person staring into a camera and talking. Though most books, even the most internal, involve more action than that.

I think there are two major things movies do that books cannot, which are two of the most important things in creating an emotionally moving story.

1. Facial Expressions

So much of emotion is conveyed in the face, and people can instantly recognize an emotion by seeing it. Books cannot show facial expressions while movies can often have close-ups directly on an actor’s face. Of course, a writer can try to describe facial expressions in a book, and some do it better than others, but facial expressions truly are one case where a picture is worth a thousand words.

2. Sound/Tone of Voice

Not only does a musical soundtrack contribute enormously to the viewing experience, but so much emotion is conveyed in the tone of someone’s voice alone. In books, however, you cannot hear the characters’ voices. Writers can try to describe the tone through description, but in some cases, tone is indescribable. You simply know it when you hear it. Or at least, it’s easier to recognize by ear than by reading a description.

Once Upon a Time in the West (pictured above) is an example of a movie that takes full advantage of its medium. Director Sergio Leone uses extreme close-ups with no dialogue at all, focusing in the actor’s faces. No dialogue is needed because their faces—their eyes particularly—say so much. Leone also uses sound to its full effect, in conjunction with musical composer Ennio Morricone. Once Upon a Time in the West is one of my favorite soundtracks because the harmonica music played throughout is integral to the actual plot.

The fact that movies are able to convey both of these emotions, the visual and auditory, is what makes the medium so powerful. It’s something books simply cannot do to the same level and effect. That doesn’t mean movies are better than books as a medium in all respects. There are likewise things books can do that film cannot, such as get fully inside a character’s head and see what, how, and why they think—capture the stream of consciousness.

No medium is absolutely better or more powerful than another, be it books, movies, video games, comic books, music, poetry, or virtual reality. Each has its strengths and weaknesses and can do things that the other cannot, which is why I enjoy them all.