> On 22 Dec 2018, at 10:00, Philip Thrift <[email protected]> wrote: > > > > On Saturday, December 22, 2018 at 2:35:27 AM UTC-6, Philip Thrift wrote: > > > On Saturday, December 22, 2018 at 1:13:48 AM UTC-6, [email protected] <> > wrote: > What are the key differences between their contributions to computer science? > TIA, AG > > A century apart: > > 1837 - Analytical Engine > 1936 - Turing Machine > > "[Charles Babbage's] Analytical Engine incorporated an arithmetic logic unit, > control flow in the form of conditional branching and loops, and integrated > memory, making it the first design for a general-purpose computer that could > be described in modern terms as Turing-complete. In other words, the logical > structure of the Analytical Engine was essentially the same as that which has > dominated computer design in the electronic era." > [ https://en.wikipedia.org/wiki/Analytical_Engine > <https://en.wikipedia.org/wiki/Analytical_Engine> ] > > Turing sort of picked up where Babbage left off 100 years before. > > In retrospect, it is surprising that programming languages (which also > logicians seemed oblivious to as well as mathematicians) took so long to > originate. > > - pt > > > > > Regarding programming, one shouldn't forget who was to be the "first > programmer" for Babbage's AE. > > Ada Augusta, Countess of Lovelace > > http://www.fourmilab.ch/babbage/sketch.html
>From a text by Jacques Lafitte from 1911, Babbage would have Been more proud >of its functional language that he invented to describe the plan of its “gear >machine”, which makes me think that he discovered the concept of “universal >machinery/universal machine”. The first to discover the universal machine explicitly is, to my knowledge Emile Post, and it includes hs understanding that “Church’s thesis”, is a form of empirical laws, to be tested infinitely often. Post anticipated the Lucas-Penrose argument, but also saw the machine response and understood the non validity of such type of arguments. Post anticipated up to the immaterialist consequence of Mechanism, but makes it appear in the subject, probably influenced by Brouwer, so he was not so sure, and change its mind after reading Turing (and coming back to a form of dualism). To sum up Babbage discovery the universal purpose machine, and almost build it, but the notion is rediscovered by the mathematicians when working on the conceptual problem in the foundations of mathematics. (Gödel’s discover the primitive recursive functions, a large subclass of thetotal computable functions, but Turing will make precise the notion of universal machine, a set of quadruplets mime-icking all set of quadruplets through their descriptions as numbers. Post, Kleene will do the equivalent work for the enumerable sets and leads to Recursion Theory and the studies of the degrees of unsolvability of the arithmetical problems. The war will motivate the buildings of such non universal, at first, but quickly universal machines: the computers (physical implementation of universal machine). Ada Lovelace can be considered as the “inventor of subroutine” and even as the first programmer, but some clock-bass machinery already occurred in the Antic world, and were quite sophisticated. Suze in Germany, von Neumann, others will be the first computers, then Steve Jobs, thanks to the quantum based discovery of the transistors and their miniaturisation. Bruno > > - pt > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/everything-list > <https://groups.google.com/group/everything-list>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
