Intention is a deliberate act of will in which we declare and commit ourselves to a new state in the universe. It does not need to be practical or even possible with our current knowledge. It does have to be something we can either believe in, or suspend our disbelief in order to allow it to come into existence.
An example of intention is when in 1961 President John F. Kennedy declared that the United States would put a man on the moon within 10 years, something thought almost impossible at the time - and a goal which turned out to be achieved in 8 years.
Another is Dr. Martin Luther King's "I Have a Dream" speech - a dream which once declared became a statement of intention whose words are still ringing in changes across the planet.
Intention is about words uttered with power and certainty - we give our intention to our Word, and so it becomes.
Ursula Le Guinn's five part Earthsea trilogy (written long before five part trilogies became popular - make sure to read the book and not the very-loosely-related DVD), starting with "A Wizard of Earthsea", is about a world where magic is common and illusion the lowest of skills. The real Mage knows the True Name of a person or thing, and in so doing is able to control it, or even call it into creation from nothing or return it to the nothingness from which it came. And the true Mage is also always aware of the balance of things, and that all acts of creation have their consequences, and are to be used wisely.

















