In recent years there has been a strong development of the concept of virtual reality (VR) which from the first video games developed in the 60s has reached the current immersive systems. VR and the consequent deception of perception pose an interesting question: is it possible to deceive the mind to the point of not being able to recognize whether the perceived reality is real or simulated? In addition to this question, another question arises spontaneously: is it possible to simulate a non-reality in which the physical laws do not apply? The answer to the first question is that it would theoretically be possible to deceive the mind to the point of not being able to recognize whether the perceived reality is real or simulated, furthermore it is also possible to simulate a non-real, i.e. magical, world. However, this possibility is based on hiding degrees of freedom from the observer, therefore it requires the complicity of the observer to be realised. It can be said that a VR system can simulate both a real and non-real experience. For an observer, a virtual reality experience is still an experience of reality. This experience can be exchanged for a different experience, that is, for a different reality that can be real or not real.