On 27 Jul 2009, at 16:07, ronaldheld wrote: > > I am following, but have not commented, because there is nothing > controversal.
Cool. Even the sixth first steps of UDA? > > When you are done, can your posts be consolidated into a paper or a > document that can be read staright through? I should do that. Bruno > On Jul 23, 9:28 am, Bruno Marchal <marc...@ulb.ac.be> wrote: >> On 23 Jul 2009, at 15:09, m.a. wrote: >> >>> Bruno, >>> Yes, yours and Brent's explanations seem very clear. I >>> hate to ask you to spell things out step by step all the way, but I >>> can tell you that when I'm confronted by a dense hedge or clump of >>> math symbols, my mind refuses to even try to disentangle them and >>> reels back in terror. So I beg you to always advance in baby steps >>> with lots of space between statements. I want to assure you that I'm >>> printing out all of your 7-step lessons and using them for study and >>> reference. Thanks for your patience, m.a. >> >> Don't worry, I understand that very well. And this illustrates also >> that your "despair" is more psychological than anything else. I have >> also abandoned the study of a mathematical book until I realize that >> the difficulty was more my bad eyesight than any conceptual >> difficulties. With good spectacles I realize the subject was not too >> difficult, but agglomeration of little symbols can give a bad >> impression, even for a mathematician. >> >> I will make some effort, tell me if my last post, on the relation >> >> (a^n) * (a^m) = a^(n + m) >> >> did help you. >> >> You are lucky to have an infinitely patient teacher. You can ask any >> question, like "Bruno, >> >> is (a^n) * (a^m) the same as a^n times a^m?" >> Answer: yes, I use often "*", "x", as shorthand for "times", and I >> use "(" and ")" as delimiters in case I fear some ambiguity. >> >> Bruno >> >> >> >> >> >> >> >>> -- Original Message ----- >>> From: Bruno Marchal >>> To: everything-list@googlegroups.com >>> Sent: Wednesday, July 22, 2009 12:20 PM >>> Subject: Re: The seven step series >> >>> Marty, >> >>> Brent wrote: >> >>> On 21 Jul 2009, at 23:24, Brent Meeker wrote: >> >>>> Take all strings of length 2 >>>> 00 01 10 11 >>>> Make two copies of each >>>> 00 00 01 01 10 10 11 11 >>>> Add a 0 to the first and a 1 to the second >>>> 000 001 010 011 100 101 110 111 >>>> and you have all strings of length 3. >> >>> Then you wrote >> >>>> I can see where adding 0 to the first and 1 to the second gives 000 >>>> and 001 and I think I see how you get 010 but the rest of the >>>> permutations don't seem obvious to me. P-l-e-a-s-e explain, Best, >> >>>> >>>> >>>> m >>>> . (mathematically hopeless) a. >> >>> Let me rewrite Brent's explanation, with a tiny tiny tiny >>> improvement: >> >>> Take all strings of length 2 >>> 00 >>> 01 >>> 10 >>> 11 >>> Make two copies of each >> >>> first copy: >>> 00 >>> 01 >>> 10 >>> 11 >> >>> second copy >>> 00 >>> 01 >>> 10 >>> 11 >> >>> add a 0 to the end of the strings in the first copy, and then add a >>> 1 to the end of the strings in the second copy: >> >>> first copy: >>> 000 >>> 010 >>> 100 >>> 110 >> >>> second copy >>> 001 >>> 011 >>> 101 >>> 111 >> >>> You get all 8 elements of B_3. >> >>> You can do the same reasoning with the subsets. Adding an element to >>> a set multiplies by 2 the number of elements of the powerset: >> >>> Exemple. take a set with two elements {a, b}. Its powerset is {{ } >>> {a} {b} {a, b}}. How to get all the subset of {a, b, c} that is the >>> set coming from adding c to {a, b}. >> >>> Write two copies of the powerset of {a, b} >> >>> { } >>> {a} >>> {b} >>> {a, b} >> >>> { } >>> {a} >>> {b} >>> {a, b} >> >>> Don't add c to the set in the first copy, and add c to the sets in >>> the second copies. This gives >> >>> { } >>> {a} >>> {b} >>> {a, b} >> >>> {c} >>> {a, c} >>> {b, c} >>> {a, b, c} >> >>> and that gives all subsets of {a, b, c}. >> >>> This is coherent with interpreting a subset {a, b} of a set {a, b, >>> c}, by a string like 110, which can be conceived as a shortand for >> >>> Is a in the subset? YES, thus 1 >>> Is b in the subset? YES thus 1 >>> Is c in the subset? NO thus 0. >> >>> OK? >> >>> You say also: >> >>>> The example of Mister X only confuses me more. >> >>> Once you understand well the present post, I suggest you reread the >>> Mister X examples, because it is a key in the UDA reasoning. If you >>> still have problem with it, I suggest you quote it, line by line, >>> and ask question. I will answer (or perhaps someone else). >> >>> Don't be afraid to ask any question. You are not mathematically >>> hopeless. You are just not familiarized with reasoning in math. It >>> is normal to go slowly. As far as you can say "I don't understand", >>> there is hope you will understand. >> >>> Indeed, concerning the UDA I suspect many in the list cannot say "I >>> don't understand", they believe it is philosophy, so they feel like >>> they could object on philosophical ground, when the whole point is >>> to present a deductive argument in a theory. So it is false, or you >>> have to accept the theorem in the theory. It is a bit complex, >>> because it is an "applied theory". The mystery are in the axioms of >>> the theory, as always. >> >>> So please ask *any* question. I ask this to everyone. I am intrigued >>> by the difficulty some people can have with such reasoning (I mean >>> the whole UDA here). (I can understand the shock when you get the >>> point, but that is always the case with new results: I completely >>> share Tegmark's idea that our brain have not been prepared to >>> have any intuition when our mind try to figure out what is behind >>> our local neighborhood). >> >>> Bruno >> >>> http://iridia.ulb.ac.be/~marchal/ >> >> http://iridia.ulb.ac.be/~marchal/- Hide quoted text - >> >> - Show quoted text - > > http://iridia.ulb.ac.be/~marchal/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. 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