According to Rene Descartes, a French philosopher and mathematician, a human can see something, but what they are seeing might not be true. The only irrefutable truth is that you are seeing. The fact that you are seeing means your brain is working. In the image above, you can see the mind at work, looking at the entity ahead. Whilst the mind might see one thing, somebody else might see another. The only thing that does not change is the fact that they are seeing, meaning their brains are working. Rene Descartes came up with the philosophical idea of cogito ergo sum, or "I think therefore I am." This relates to the image because the mind is thinking of what it is looking at, which means that the person is there, and not in a state of unconsciousness.