I once dreamed that I was following my own Grandiocosmic String to its source, pulling myself downward, hand-over-hand. I was heading toward a place of ultimate meaning, perhaps Ark itself. But then my hand grabbed onto the part of the string responsible for creating the dream, and I woke. I wish I hadn't grabbed it so hard.
Isaac is 21,500 turns old.
Isaac served three different sides over a long career. Popped in Scytale, he was eventually traded in a diplomatic agreement with Viagara Falls. After more then 5000 turns there, he was captured by the Republic Domain, turned, and resided there until his release when the side suddenly expired 7,600 turns ago.
Although he was always a competent and reliable Thinkamancer, it was only as a barbarian caster that he discovered an interest in the fundamentals of magic and to explore his discipline. He was accepted early into the Great Minds that Think Alike, who appreciated his calm and polite demeanor as much as his intellect.
As he turned his studies to other forms of Eyemancy, Isaac made some deeply disturbing observations and discoveries. In particular he discovered important implications about Charlie's attunement to the Arkendish. These revelations began to turn the Great Minds away from the petty gossip of the Magic Kingdom and toward the exploration of broader questions about their world.
Isaac often hires out to sides all over Erfworld, but prefers short contracts. By means of his long lifetime of active casting, he recently achieved the rarely reached level of 11. Although this makes him the highest Headmaster in the Magic Kingdom, Isaac leads only when necessary. His mind is usually elsewhere.
 Proposed Canon
He suspected it might be a law of Erfworld, but there was not enough evidence.
Strengths: Curiosity, Generosity, Inventiveness, Building Scientific Instruments, Stylish Jackets
Weaknesses: Loneliness, Focus, Courage of Convictions
First Appearance: TBFGK 140
Isaac is a rarity among the casters of the Magic Kingdom, not content with debating and arguing over theories and hypotheses on the nature of magic and Erf, but actively working to discern reliable and consistent facts. So far, this has led to the creation of a number of devices to aid thinkamancers in better accessing nodes of amplification or attuning to the frequencies of certain G-String vibrations (all of which resemble children's playground equipment from our world).
Isaac is friendly with the Predictamancers, which has lead to a degree of fatalism in his world view.
Should he ever link up with a Carnymancer, they will create devices capable of automatically switching Thinkamancers between nodes at precisely calibrated frequencies to achieve Thinkamancy that, while not as versatile, will actually rival the Arkendish in power (like a Ferris Wheel or a Roller Coaster).
 Real World References
His name coupled with his tendencies as a natural philosopher are a reference to Isaac Newton. Some of his suspicions about the laws of Erfworld include that there is "A counter-force for every force, a reaction to every action. Opposite, and perhaps equal." which is one way of specifying the real world (Isaac Newton's) Third Law of Motion.
His appearance is a reference to Carl Sagan.
Isaac was popped in Scytale. A scytale is a tool used to perform a transposition cipher. It's a cylinder with a strip of parchment wound around it on which is written a message. The ancient Greeks, and the Spartans in particular, are said to have used this cipher to communicate during military campaigns.
The recipient uses a cylinder of the same diameter as the one on which the message was written to read the message. It has the advantage of being fast and not prone to mistakes—a necessary property when on the battlefield. It can, however, be easily broken. Since the strip of parchment hints strongly at the method, the cipher text would have to be transferred to something less suggestive, somewhat reducing the advantage noted.
His desire for the Arkendish as a tool of observation may also be a reference the use of radio telescopes in astronomy.
Both Carl Sagan and Isaac Newton were teachers, and one of the titles for the person in charge of a school is Headmaster.
Before he tells Parson his name, Parson calls him Mr.Rogers which he does kind of resemble, but he is younger looking.
Viagra Falls is a reference to both the drug, Viagra, and Niagara Falls. His 'diplomatic trade' could be a reference to the fact that one portion of Niagara Falls lies in Canada and the other lies in the United States.
The Republic Domain is likely a reference to the Dominican Republic.
ISAAC(acronym for indirection, shift, accumulate, add, and count) is a cryptographically secure pseudorandom number generator and a stream cipher designed by Robert J. Jenkins Jr. in 1996.