<p>It is improbable that one would obey a necessity if it did not bring yet other advantages beyond those issuing merely from its minimal requirements; it is also improbable that an advantage would appear that is not attached to the fulfilment of certain necessities. This looks mysterious, and is indeed so: that one does something because necessity compels it and thereby unintentionally produces beauty; or that one has the impulse to create something beautiful and thereby fulfils necessity. It is one of those mysteries that make life worth living.</p>