<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
		>
<channel>
	<title>Comments on: ampliative deduction</title>
	<atom:link href="http://www.aboutlogic.info/ampliative-deduction/feed" rel="self" type="application/rss+xml" />
	<link>http://www.aboutlogic.info/ampliative-deduction</link>
	<description>logic, math, philosophy, math games, math help, mathematical logic, philosophy of education, math facts</description>
	<lastBuildDate>Fri, 03 Feb 2012 10:40:13 +0000</lastBuildDate>
	<sy:updatePeriod>hourly</sy:updatePeriod>
	<sy:updateFrequency>1</sy:updateFrequency>
	<generator>http://wordpress.org/?v=3.3.1</generator>
	<item>
		<title>By: admin</title>
		<link>http://www.aboutlogic.info/ampliative-deduction/comment-page-1#comment-781</link>
		<dc:creator>admin</dc:creator>
		<pubDate>Mon, 30 Nov 2009 16:54:59 +0000</pubDate>
		<guid isPermaLink="false">http://www.aboutlogic.info/ampliative-deduction#comment-781</guid>
		<description>
  &lt;p&gt;In article &lt;1993Jun18.115720.6...@gps.leeds.ac.uk&gt; n...@scs.leeds.ac.uk (Nik Silver) writes: &lt;br /&gt; &lt;br /&gt;[...] &lt;br /&gt; &lt;/p&gt;&lt;p&gt;&gt; &#160;... The true explanation is very simple. The power of logic and &lt;br /&gt; &gt; &#160;mathematics to surprise us depends, like their usefulness, on the &lt;br /&gt; &gt; &#160;limitations of our reason. A being whose intellect was infinitely more &lt;br /&gt; &gt; &#160;powerful would take no interest in logic and mathematics. For he would &lt;br /&gt; &gt; &#160;be able to see at a glance everything that his definitions implied, and, &lt;br /&gt; &gt; &#160;accordingly, could never learn anything from logical inference which he &lt;br /&gt; &gt; &#160;was not fully conscious of already. &lt;br /&gt; &lt;/p&gt;&lt;p&gt;&gt;Nik Silver. &lt;br /&gt; &lt;br /&gt;In fact, this is not correct, if means of expression expand as well as &lt;br /&gt; means of reasoning. &#160;Analogues of Godel&#039;s theorem would continue to &lt;br /&gt; hold, and there would still be things which were &quot;easy&quot; and &quot;hard&quot; for &lt;br /&gt; the hypothetical infinite intellect to prove; it would simply be the &lt;br /&gt; case that everything that we can express would fall in the (trivially) &lt;br /&gt; &quot;easy&quot; category. &lt;br /&gt; &lt;/p&gt;&lt;p&gt;For the analogues of Godel&#039;s theorem not to hold, the infinite &lt;br /&gt; intellect X would have to be unable to refer to his own techniques of &lt;br /&gt; proof (among other limitations). &lt;br /&gt; &lt;/p&gt;&lt;p&gt;-- &lt;br /&gt; The opinions expressed &#160; &#160; &#160; &#160; &#160;&#124; &#160; &#160; --Sincerely, &lt;br /&gt; above are not the &quot;official&quot; &#160;&#124; &#160; &#160; M. Randall Holmes &lt;br /&gt; opinions of any person &#160; &#160; &#160; &#160; &#160;&#124; &#160; &#160; Math. Dept., Boise State Univ. &lt;br /&gt; or institution. &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#124; &#160; &#160; hol...@math.idbsu.edu &lt;br /&gt;
  
  &lt;/p&gt;</description>
		<content:encoded><![CDATA[<p>In article &lt;1993Jun18.115720.6&#8230;@gps.leeds.ac.uk&gt; <a href="mailto:n...@scs.leeds.ac.uk">n&#8230;@scs.leeds.ac.uk</a> (Nik Silver) writes: </p>
<p>[...]  </p>
<p>&gt; &nbsp;&#8230; The true explanation is very simple. The power of logic and <br /> &gt; &nbsp;mathematics to surprise us depends, like their usefulness, on the <br /> &gt; &nbsp;limitations of our reason. A being whose intellect was infinitely more <br /> &gt; &nbsp;powerful would take no interest in logic and mathematics. For he would <br /> &gt; &nbsp;be able to see at a glance everything that his definitions implied, and, <br /> &gt; &nbsp;accordingly, could never learn anything from logical inference which he <br /> &gt; &nbsp;was not fully conscious of already.  </p>
<p>&gt;Nik Silver. </p>
<p>In fact, this is not correct, if means of expression expand as well as <br /> means of reasoning. &nbsp;Analogues of Godel&#8217;s theorem would continue to <br /> hold, and there would still be things which were &quot;easy&quot; and &quot;hard&quot; for <br /> the hypothetical infinite intellect to prove; it would simply be the <br /> case that everything that we can express would fall in the (trivially) <br /> &quot;easy&quot; category.  </p>
<p>For the analogues of Godel&#8217;s theorem not to hold, the infinite <br /> intellect X would have to be unable to refer to his own techniques of <br /> proof (among other limitations).  </p>
<p>&#8211; <br /> The opinions expressed &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;| &nbsp; &nbsp; &#8211;Sincerely, <br /> above are not the &quot;official&quot; &nbsp;| &nbsp; &nbsp; M. Randall Holmes <br /> opinions of any person &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;| &nbsp; &nbsp; Math. Dept., Boise State Univ. <br /> or institution. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; <a href="mailto:hol...@math.idbsu.edu">hol&#8230;@math.idbsu.edu</a> </p>
]]></content:encoded>
	</item>
	<item>
		<title>By: admin</title>
		<link>http://www.aboutlogic.info/ampliative-deduction/comment-page-1#comment-780</link>
		<dc:creator>admin</dc:creator>
		<pubDate>Mon, 30 Nov 2009 16:54:58 +0000</pubDate>
		<guid isPermaLink="false">http://www.aboutlogic.info/ampliative-deduction#comment-780</guid>
		<description>
  &lt;p&gt;Donald Peterson (D.M.Peter...@cs.bham.ac.uk) wrote: &lt;br /&gt; &gt;Valid deductive inference is subject to a seeming paradox. &lt;br /&gt; &gt; [...seeming paradox deleted...] &lt;br /&gt; &lt;/p&gt;&lt;p&gt;&gt;Some of the logicians who have discussed this issue in a traditional &lt;br /&gt; &gt;context are CS Peirce, JS Mill, G Frege, M Dummett and W Salmon. &lt;br /&gt; &lt;br /&gt;You can also add A. J. Ayer&#039;s name to the list. Ayer refused to &lt;br /&gt; believe the paradox, offering a rather down-to-earth solution. This is from &lt;br /&gt; his ``Language, Truth and Logic&#039;&#039; pp. 81--82 (reprinted by Pelican Books). &lt;br /&gt; After suggesting that proving 7+5=12 does not tell us anything we didn&#039;t &lt;br /&gt; (at least implicitly) know already, because 12 is defined precisely to be &lt;br /&gt; 7+5, he says.... &lt;br /&gt; &lt;/p&gt;&lt;p&gt;&#160; What is mysterious at first sight is that these tautologies should on &lt;br /&gt; &#160; occasion be so surprising, that there should be in mathematics and logic &lt;br /&gt; &#160; the possibility of invention and discovery. As Poincare says: `If all the &lt;br /&gt; &#160; assertions which mathematics puts forward can be derived from one another &lt;br /&gt; &#160; by formal logic, mathematics cannot amount to anything more than an &lt;br /&gt; &#160; immense tautology. Logical inference can teach us nothing essentially new, &lt;br /&gt; &#160; and if everything is to proceed from the priciple of identity, everything &lt;br /&gt; &#160; must be reducible to it. But can we really allow that these theorems which &lt;br /&gt; &#160; fill so many books serve no other purpose than to say in a roundabout &lt;br /&gt; &#160; fashion ``A=A&#039;&#039; ?&#039; ... &lt;br /&gt; &#160; ... The true explanation is very simple. The power of logic and &lt;br /&gt; &#160; mathematics to surprise us depends, like their usefulness, on the &lt;br /&gt; &#160; limitations of our reason. A being whose intellect was infinitely more &lt;br /&gt; &#160; powerful would take no interest in logic and mathematics. For he would &lt;br /&gt; &#160; be able to see at a glance everything that his definitions implied, and, &lt;br /&gt; &#160; accordingly, could never learn anything from logical inference which he &lt;br /&gt; &#160; was not fully conscious of already. &lt;br /&gt; &lt;/p&gt;&lt;p&gt;Nik Silver. &lt;br /&gt;
  
  &lt;/p&gt;</description>
		<content:encoded><![CDATA[<p>Donald Peterson (D.M.Peter&#8230;@cs.bham.ac.uk) wrote: <br /> &gt;Valid deductive inference is subject to a seeming paradox. <br /> &gt; [...seeming paradox deleted...]  </p>
<p>&gt;Some of the logicians who have discussed this issue in a traditional <br /> &gt;context are CS Peirce, JS Mill, G Frege, M Dummett and W Salmon. </p>
<p>You can also add A. J. Ayer&#8217;s name to the list. Ayer refused to <br /> believe the paradox, offering a rather down-to-earth solution. This is from <br /> his &#8220;Language, Truth and Logic&#8221; pp. 81&#8211;82 (reprinted by Pelican Books). <br /> After suggesting that proving 7+5=12 does not tell us anything we didn&#8217;t <br /> (at least implicitly) know already, because 12 is defined precisely to be <br /> 7+5, he says&#8230;.  </p>
<p>&nbsp; What is mysterious at first sight is that these tautologies should on <br /> &nbsp; occasion be so surprising, that there should be in mathematics and logic <br /> &nbsp; the possibility of invention and discovery. As Poincare says: `If all the <br /> &nbsp; assertions which mathematics puts forward can be derived from one another <br /> &nbsp; by formal logic, mathematics cannot amount to anything more than an <br /> &nbsp; immense tautology. Logical inference can teach us nothing essentially new, <br /> &nbsp; and if everything is to proceed from the priciple of identity, everything <br /> &nbsp; must be reducible to it. But can we really allow that these theorems which <br /> &nbsp; fill so many books serve no other purpose than to say in a roundabout <br /> &nbsp; fashion &#8220;A=A&#8221; ?&#8217; &#8230; <br /> &nbsp; &#8230; The true explanation is very simple. The power of logic and <br /> &nbsp; mathematics to surprise us depends, like their usefulness, on the <br /> &nbsp; limitations of our reason. A being whose intellect was infinitely more <br /> &nbsp; powerful would take no interest in logic and mathematics. For he would <br /> &nbsp; be able to see at a glance everything that his definitions implied, and, <br /> &nbsp; accordingly, could never learn anything from logical inference which he <br /> &nbsp; was not fully conscious of already.  </p>
<p>Nik Silver. </p>
]]></content:encoded>
	</item>
	<item>
		<title>By: admin</title>
		<link>http://www.aboutlogic.info/ampliative-deduction/comment-page-1#comment-779</link>
		<dc:creator>admin</dc:creator>
		<pubDate>Mon, 30 Nov 2009 16:54:57 +0000</pubDate>
		<guid isPermaLink="false">http://www.aboutlogic.info/ampliative-deduction#comment-779</guid>
		<description>
  &lt;p&gt;In article &lt;C8rsIB....@cs.bham.ac.uk&gt; D.M.Peter...@cs.bham.ac.uk (Donald Peterson) writes: &lt;br /&gt; &lt;br /&gt;&#160; &#160;Valid deductive inference is subject to a seeming paradox. &#160;(1) The &lt;br /&gt; &#160; &#160;content of the conclusion is already stated or &#039;contained&#039; in the &lt;br /&gt; &#160; &#160;premises ... , and so such arguments are &#039;non-ampliative&#039;. But (2) such &lt;br /&gt; &#160; &#160;arguments can give us something new and useful and &lt;br /&gt; &#160; &#160;so would seem to be in some sense ampliative. &lt;br /&gt; &lt;/p&gt;&lt;p&gt;From an AI point of view there is no paradox here - the theorem that &lt;br /&gt; is &quot;contained&quot; in a set of premises is only there *implicitly*, and is &lt;br /&gt; made *explicitly* available only if and when it is deduced. &#160;For many &lt;br /&gt; real-world purposes and real-world information users (e.g., people or &lt;br /&gt; programs), information cannot be used unless it available in some &lt;br /&gt; particular explicit form. &#160;Even if the information users have some &lt;br /&gt; limited deductive ability, and can on their own make *some* implicit &lt;br /&gt; things explicit, they rarely have the ability to compute the full &lt;br /&gt; deductive closure of a theory (at least, to do so fast enough to be &lt;br /&gt; useful). &#160;Thus, the theorem may not be usable while &quot;contained&quot; &lt;br /&gt; implicitly in the premises, but it may be very usable once it is &lt;br /&gt; explicitly present in the derivation, or at least once something from &lt;br /&gt; which it can be derived by a specific limited deductive process is &lt;br /&gt; present. &lt;br /&gt; &lt;/p&gt;&lt;p&gt;Traditionally logic has dealt with issues where a theorem implicitly &lt;br /&gt; present was just as powerful as one explicitly present (e.g. in &lt;br /&gt; defining terms like &quot;consistent&quot;, &quot;complete&quot;, &quot;model&quot;, ...), Perhaps &lt;br /&gt; this assumption has become so embedded in your worldview that you no &lt;br /&gt; longer remember you are making it. &#160;(It has become implicit :-) &lt;br /&gt; -- &lt;br /&gt; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; &#160; Lou Steinberg &lt;br /&gt; &lt;/p&gt;&lt;p&gt;uucp: &#160; {pretty much any major site}!rutgers!aramis.rutgers.edu!lou &lt;br /&gt; internet: &#160; l...@cs.rutgers.edu &lt;br /&gt;
  
  &lt;/p&gt;</description>
		<content:encoded><![CDATA[<p>In article &lt;C8rsIB&#8230;.@cs.bham.ac.uk&gt; <a href="mailto:D.M.Peter...@cs.bham.ac.uk">D.M.Peter&#8230;@cs.bham.ac.uk</a> (Donald Peterson) writes: </p>
<p>&nbsp; &nbsp;Valid deductive inference is subject to a seeming paradox. &nbsp;(1) The <br /> &nbsp; &nbsp;content of the conclusion is already stated or &#8216;contained&#8217; in the <br /> &nbsp; &nbsp;premises &#8230; , and so such arguments are &#8216;non-ampliative&#8217;. But (2) such <br /> &nbsp; &nbsp;arguments can give us something new and useful and <br /> &nbsp; &nbsp;so would seem to be in some sense ampliative.  </p>
<p>From an AI point of view there is no paradox here &#8211; the theorem that <br /> is &quot;contained&quot; in a set of premises is only there *implicitly*, and is <br /> made *explicitly* available only if and when it is deduced. &nbsp;For many <br /> real-world purposes and real-world information users (e.g., people or <br /> programs), information cannot be used unless it available in some <br /> particular explicit form. &nbsp;Even if the information users have some <br /> limited deductive ability, and can on their own make *some* implicit <br /> things explicit, they rarely have the ability to compute the full <br /> deductive closure of a theory (at least, to do so fast enough to be <br /> useful). &nbsp;Thus, the theorem may not be usable while &quot;contained&quot; <br /> implicitly in the premises, but it may be very usable once it is <br /> explicitly present in the derivation, or at least once something from <br /> which it can be derived by a specific limited deductive process is <br /> present.  </p>
<p>Traditionally logic has dealt with issues where a theorem implicitly <br /> present was just as powerful as one explicitly present (e.g. in <br /> defining terms like &quot;consistent&quot;, &quot;complete&quot;, &quot;model&quot;, &#8230;), Perhaps <br /> this assumption has become so embedded in your worldview that you no <br /> longer remember you are making it. &nbsp;(It has become implicit <img src='http://www.aboutlogic.info/wp-includes/images/smilies/icon_smile.gif' alt=':-)' class='wp-smiley' />  <br /> &#8212; <br /> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Lou Steinberg  </p>
<p>uucp: &nbsp; {pretty much any major site}!rutgers!aramis.rutgers.edu!lou <br /> internet: &nbsp; <a href="mailto:l...@cs.rutgers.edu">l&#8230;@cs.rutgers.edu</a> </p>
]]></content:encoded>
	</item>
</channel>
</rss>

