There are several reasons why we have only two eyes. One reason is that having two eyes provides us with binocular vision, which means that we have the ability to see objects in three dimensions. This is because each eye sees the world from a slightly different perspective, and the brain is able to combine the two images to form a single, three-dimensional image.
Another reason why we have only two eyes is that they are positioned on opposite sides of the head, which gives us a wide field of view. This is important for survival, as it allows us to see predators or prey that may be lurking on the edges of our vision.
Finally, having two eyes also allows us to judge distances more accurately. This is because each eye sends a slightly different image to the brain, and the brain is able to use these two images to calculate the distance of objects. This is important for activities such as hunting or driving, where we need to be aware of our surroundings and know how far away things are.