Question: The physicist who made an argument with Enrico Fermi against the existence of extraterrestrial civilizations has described himself as what?

Context paragraphs:
Fermi problem: In physics or engineering education, a Fermi problem, Fermi quiz, Fermi question, Fermi estimate, or order estimation is an estimation problem designed to teach dimensional analysis, approximation, and such a problem is usually a back-of-the-envelope calculation.  The estimation technique is named after physicist Enrico Fermi as he was known for his ability to make good approximate calculations with little or no actual data.  Fermi problems typically involve making justified guesses about quantities and their variance or lower and upper bounds.

Great Filter: The Great Filter, in the context of the Fermi paradox, is whatever prevents "dead matter" from giving rise, in time, to "expanding lasting life".  The concept originates in Robin Hanson's argument that the failure to find any extraterrestrial civilizations in the observable universe implies the possibility something is wrong with one or more of the arguments from various scientific disciplines that the appearance of advanced intelligent life is probable; this observation is conceptualized in terms of a "Great Filter" which acts to reduce the great number of sites where intelligent life might arise to the tiny number of intelligent species with advanced civilizations actually observed (currently just one: human).  This probability threshold, which could lie behind us (in our past) or in front of us (in our future), might work as a barrier to the evolution of intelligent life, or as a high probability of self-destruction.  The main counter-intuitive conclusion of this observation is that the easier it was for life to evolve to our stage, the bleaker our future chances probably are.

Michael H. Hart: Michael H. Hart (born April 27, 1932) is an American astrophysicist and author, most notably of "The 100: A Ranking of the Most Influential Persons in History".  He has described himself as a white separatist and is active in white separatist causes.

Enfield High School: Enfield High School is a secondary school established in 1893 in Enfield, Connecticut.  The Enfield High School campus is located in the Connecticut River Valley, on Enfield Street (U.S. Route 5) in Enfield's Historical District.  The school has an enrollment of approximately 1400 students.  The present facility was built in 1964 on Enfield Street.  The facility underwent a $6.2 million renovation and library addition completed in 2005, and a $103 million "as-new" renovation and significant expansion completed in 2017.  In May 2010, Enfield High School and Enrico Fermi High School underwent a consolidation process as part of the restructuring and improvement plan of Enfield Public Schools.  Enfield High School operates as the town's sole high school, which houses both students from Enfield High School and the previous Enrico Fermi High School, which closed its doors in 2016.

Enrico Fermi Institute: The Institute for Nuclear Studies was founded September 1945 as part of the University of Chicago with Samuel King Allison as director.  On November 20, 1955 it was renamed The Enrico Fermi Institute for Nuclear Studies.  The name was shortened to The Enrico Fermi Institute (EFI) in January 1968.

Enrico Fermi Award: The Enrico Fermi Award is an award honoring scientists of international stature for their lifetime achievement in the development, use, or production of energy.  It is administered by the U.S. government's Department of Energy.  The recipient receives $50,000, a certificate signed by the President and the Secretary of Energy, and a gold medal featuring the likeness of Enrico Fermi.

Drake equation: The Drake equation is a probabilistic argument used to estimate the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy.

Extraterrestrial Civilizations: Extraterrestrial Civilizations is a 1979 book by Isaac Asimov, in which Asimov estimates the probability of there being intelligent extraterrestrial civilizations within the Milky Way galaxy.  This estimation is approached by progressively analyzing the requirements for life to exist.

Fermi paradox: The Fermi paradox or Fermi's paradox, named after physicist Enrico Fermi, is the apparent contradiction between the lack of evidence and high probability estimates, for the existence of extraterrestrial civilizations.  The basic points of the argument, made by physicists Enrico Fermi (1901–1954) and Michael H. Hart (born 1932), are:

Herbert L. Anderson: Herbert Lawrence Anderson (May 24, 1914 – July 16, 1988) was an American nuclear physicist who contributed to the Manhattan Project.  He was also a member of the team which made the first demonstration of nuclear fission in the United States, in the basement of Pupin Hall at Columbia University.  He participated in the first atomic bomb test, codenamed Trinity.  After the close of World War II, he was a professor of physics at the University of Chicago until 1982.  There, he helped Fermi establish the Enrico Fermi Institute and was its director from 1958 to 1962.  The latter part of his career was as a senior fellow at Los Alamos National Laboratory.  He was a recipient of the Enrico Fermi Award.  Anderson's lineage to Rabbi Meir Katzenellenbogen, the Maharam of Padua, is detailed in "The Unbroken Chain".

Supporting paragraphs: Fermi paradox Michael H. Hart
Answer: a white separatist