It's nice to get a Kindle Fire for Christmas and have 5 solid days off due to the holidays to waste watching television series which I previously haven't had time to do.
I can see the argument for Walter typing as an Intj. However, the reason why I typed him Istj is due to the overall history of his life. Since most of his adult life up until his cancer diagnoses he presents as a typical responsible and dutiful suburban family man/science teacher he seemed more of an Istj. I'm not seeing any evidence of his fitting the role of the mastermind NT, outside of his intelligence with regards to science and chemistry. I would expect an Intj would have chosen a career field which would have been higher up on the academic scale or more scientifically oriented. He also had some sort of tie in with his old college schoolmate and business/academics which either has not been fully brought to light in the first season, or I missed. I question why (if he were an Intj) he would not have pursued unless he valued his family life and career as a science teacher above his personal interests and goals. Also the entire approach with which he initially decides to operate a clandestine meth lab and become involved in producing methamphetamines lacks the well thought out planning which I would expect more from an Intj.
Okay, I concede to his type as Intj since his drug alias "Heisenburg" is after theoretical physicist "Werner Karl Heisenberg (German: [ˈhaɪzənbɛɐ̯k]; 5 December 1901 – 1 February 1976) was a German theoretical physicist and one of the key pioneers of quantum mechanics. He published his work in 1925 in a breakthrough paper. In the subsequent series of papers with Max Born and Pascual Jordan, during the same year, this matrix formulation of quantum mechanics was substantially elaborated. In 1927 he published his uncertainty principle, upon which he built his philosophy and for which he is best known. Heisenberg was awarded the Nobel Prize in Physics for 1932 "for the creation of quantum mechanics". He also made important contributions to the theories of the hydrodynamics of turbulent flows, the atomic nucleus, ferromagnetism, cosmic rays, and subatomic particles, and he was instrumental in planning the first West German nuclear reactor at Karlsruhe, together with a research reactor in Munich, in 1957. Considerable controversy surrounds his work on atomic research during World War II.
Following World War II, he was appointed director of the Kaiser Wilhelm Institute for Physics, which soon thereafter was renamed the Max Planck Institute for Physics. He was director of the institute until it was moved to Munich in 1958, when it was expanded and renamed the Max Planck Institute for Physics and Astrophysics.
Heisenberg was also president of the German Research Council, chairman of the Commission for Atomic Physics, chairman of the Nuclear Physics Working Group, and president of the Alexander von Humboldt Foundation."