Comment logic is wrong in Listing 18

[Rickfdalton]

In Listing 18: Remembering the side of the surface

bool front_face;
if (dot(ray_direction, outward_normal) > 0.0) {
    // ray is inside the sphere
    normal = -outward_normal;
    front_face = false;
} else {
    // ray is outside the sphere
    normal = outward_normal;
    front_face = true;
}

The dot product between the outward_normal and the ray_direction being positive implies the point in in the backside of the sphere and negative implies the point in in the frontside of the sphere. But the comment says the ray is inside/outside. This is ambiguous.