Editing Entscheidungsproblem (section)

== History ==
The origin of the {{lang|de|Entscheidungsproblem}} goes back to [[Gottfried Leibniz]], who in the seventeenth century, after having constructed a successful mechanical [[calculating machine]], dreamt of building a machine that could manipulate symbols in order to determine the [[truth value]]s of mathematical statements.<ref>{{harvnb|Davis|2001|pp=3–20}}</ref> He realized that the first step would have to be a clean [[formal language]], and much of his subsequent work was directed toward that goal. In 1928, [[David Hilbert]] and [[Wilhelm Ackermann]] posed the question in the form outlined above.

In continuation of his "program", Hilbert posed three questions at an international conference in 1928, the third of which became known as "Hilbert's {{lang|de|Entscheidungsproblem}}".<ref>{{harvnb|Hodges|1983|p=91}}</ref> In 1929, [[Moses Schönfinkel]] published one paper on special cases of the decision problem, that was prepared by [[Paul Bernays]].<ref name="Kline">{{Citation | first1=G. L. | last1=Kline | title=Review of Foundations of mathematics and mathematical logic by S. A. Yanovskaya | journal=[[Journal of Symbolic Logic]] | volume=16 | pages=46–48 | year=1951 | doi=10.2307/2268665 | jstor=2268665 | issue=1 | last2=Anovskaa | first2=S. A.| s2cid=119004002 }}</ref>

As late as 1930, Hilbert believed that there would be no such thing as an unsolvable problem.<ref>{{harvnb|Hodges|1983|p=92}}, quoting from Hilbert</ref>