Editing David Hilbert (section)

===Personal life===
[[File:ConstantinCaratheodory KatheHilbert MFO633.jpg|thumb|Käthe Hilbert with [[Constantin Carathéodory]], before 1932]]
{{Multiple image| image1 = David Hilbert and Käthe Jerosch.png| image2 = FranzHilbert MFO.jpg| caption2 = Franz Hilbert| caption1 = Hilbert and his wife Käthe Jerosch (1892)| direction = horizontal| align = left| total_width = 370}}
In 1892, Hilbert married Käthe Jerosch (1864–1945), who was the daughter of a Königsberg merchant, "an outspoken young lady with an independence of mind that matched [Hilbert's]."{{Sfn|Reid|1996|p=[https://books.google.com/books?id=mR4SdJGD7tEC&pg=PA36 36]}} While at Königsberg, they had their one child, Franz Hilbert (1893–1969).
Franz suffered throughout his life from mental illness, and after he was admitted into a psychiatric clinic, Hilbert said, "From now on, I must consider myself as not having a son." His attitude toward Franz brought Käthe considerable sorrow.{{Sfn|Reid|1996|p=[https://books.google.com/books?id=mR4SdJGD7tEC&pg=PA139 139]}}

Hilbert considered the mathematician [[Hermann Minkowski]] to be his "best and truest friend".{{Sfn|Reid|1996|p=121}}

Hilbert was baptized and raised a [[Calvinist]] in the [[Prussian Union of churches|Prussian Evangelical Church]].<ref group=lower-alpha>The Hilberts had, by this time, left the Calvinist Protestant church in which they had been baptized and married. – Reid 1996, p.91</ref> He later left the Church and became an [[agnostic]].<ref name=hilbertagnostic group=lower-alpha>
David Hilbert seemed to be agnostic and had nothing to do with theology proper or even religion. Constance Reid tells a story on the subject:<blockquote>The Hilberts had by this time [around 1902] left the Reformed Protestant Church in which they had been baptized and married. It was told in Göttingen that when [David Hilbert's son] Franz had started to school he could not answer the question, "What religion are you?" (1970, p.&nbsp;91)</blockquote> In the 1927 Hamburg address, Hilbert asserted: "mathematics is pre-suppositionless science (die Mathematik ist eine voraussetzungslose Wissenschaft)" and "to found it I do not need a good God ([z]u ihrer Begründung brauche ich weder den lieben Gott)" (1928, S. 85; van Heijenoort, 1967, p.&nbsp;479). However, from Mathematische Probleme (1900) to Naturerkennen und Logik (1930) he placed his quasi-religious faith in the human spirit and in the power of pure thought with its beloved child– mathematics. He was deeply convinced that every mathematical problem could be solved by pure reason: in both mathematics and any part of natural science (through mathematics) there was "no ignorabimus" (Hilbert, 1900, S. 262; 1930, S. 963; Ewald, 1996, pp. 1102, 1165). That is why finding an inner absolute grounding for mathematics turned into Hilbert's life-work. He never gave up this position, and it is symbolic that his words "wir müssen wissen, wir werden wissen" ("we must know, we shall know") from his 1930 Königsberg address were engraved on his tombstone. Here, we meet a ghost of departed theology (to modify George Berkeley's words), for to absolutize human cognition means to identify it tacitly with a divine one. —{{cite journal
 | last = Shaposhnikov  | first = Vladislav
 | year = 2016
 | title = Theological Underpinnings of the Modern Philosophy of Mathematics. Part II: The Quest for Autonomous Foundations
 | journal = Studies in Logic, Grammar and Rhetoric
 | volume = 44  | issue = 1  | pages = 147–168
 | doi = 10.1515/slgr-2016-0009  | doi-access = free
}}
</ref> He also argued that mathematical truth was independent of the existence of God or other ''[[A priori and a posteriori|a priori]]'' assumptions.<ref group=lower-alpha>"Mathematics is a presuppositionless science. To found it I do not need God, as does Kronecker, or the assumption of a special faculty of our understanding attuned to the principle of mathematical induction, as does Poincaré, or the primal intuition of Brouwer, or, finally, as do Russell and Whitehead, axioms of infinity, reducibility, or completeness, which in fact are actual, contentual assumptions that cannot be compensated for by consistency proofs." David Hilbert, ''Die Grundlagen der Mathematik'', [http://people.cs.uchicago.edu/~odonnell/OData/Courses/22C:096/Lecture_notes/Hilbert_program.html Hilbert's program, 22C:096, University of Iowa].</ref><ref group=lower-alpha>{{cite book|title=Science, Worldviews and Education|year=2009|publisher=Springer|isbn=978-90-481-2779-5|page=129|author=Michael R. Matthews|quote=As is well known, Hilbert rejected Leopold Kronecker's God for the solution of the problem of the foundations of mathematics.}}</ref> When [[Galileo Galilei]] was criticized for failing to stand up for his convictions on the [[Heliocentric theory]], Hilbert objected: "But [Galileo] was not an idiot. Only an idiot could believe that scientific truth needs martyrdom; that may be necessary in religion, but scientific results prove themselves in due time."<ref group=lower-alpha>{{cite book |author1=Constance Reid |author2=Hermann Weyl |title=Hilbert |url=https://archive.org/details/hilbert0000reid_e2z0 |url-access=registration |date=1970 |publisher=Springer-Verlag |isbn=978-0-387-04999-1 |page=[https://archive.org/details/hilbert0000reid_e2z0/page/92 92] |quote=Perhaps the guests would be discussing Galileo's trial and someone would blame Galileo for failing to stand up for his convictions. "But he was not an idiot," Hilbert would object. "Only an idiot could believe that scientific truth needs martyrdom; that may be necessary in religion, but scientific results prove themselves in due time."}}</ref>