<!DOCTYPE html><HTML lang="en"> <head><meta charset="utf-8"> <title>Nelson (Jack) - Logically Necessary and Sufficient Conditions for Identity through Time (Theo Todman's Book Collection - Paper Abstracts) </title> <link href="../../TheosStyle.css" rel="stylesheet" type="text/css"><link rel="shortcut icon" href="../../TT_ICO.png" /></head> <BODY> <CENTER> <div id="header"><HR><h1>Theo Todman's Web Page - Paper Abstracts</h1><HR></div><A name="Top"></A> <TABLE class = "Bridge" WIDTH=950> <tr><th><A HREF = "../../PaperSummaries/PaperSummary_05/PaperSummary_5988.htm">Logically Necessary and Sufficient Conditions for Identity through Time</A></th></tr> <tr><th><A HREF = "../../Authors/N/Author_Nelson (Jack).htm">Nelson (Jack)</a></th></tr> <tr><th>Source: American Philosophical Quarterly, 9(2), 1972, pp. 177-185</th></tr> <tr><th>Paper - Abstract</th></tr> </TABLE> </CENTER> <P><CENTER><TABLE class = "Bridge" WIDTH=200><tr><td><A HREF = "../../PaperSummaries/PaperSummary_05/PaperSummary_5988.htm">Paper Summary</A></td></tr></TABLE></CENTER></P> <hr><P><FONT COLOR = "0000FF"><U>Philosophers Index Abstract</U><FONT COLOR = "800080"><ol type="1"><a name="1"></a><A HREF="../../Notes/Notes_0/Notes_81.htm">Leibniz's law</A><SUP>1</SUP> and the <a name="2"></a><A HREF="../../Notes/Notes_0/Notes_81.htm">identity of indiscernibles</A><SUP>2</SUP> principle together yield a necessary and sufficient condition for identity, but one which is so general as to be almost useless. It is commonly thought that there must also be more specific conditions for identity, e.G., For the identity of material objects through time. It is argued that this is not the case, at least as regards material objects, since any such condition would have to rely on the relation of spatio-temporal continuity and that relation cannot be explicated in any useable way.</ol></FONT><FONT COLOR = "0000FF"><HR></P><a name="ColourConventions"></a><p><b>Text Colour Conventions (see <A HREF="../../Notes/Notes_10/Notes_1025.htm">disclaimer</a>)</b></p><OL TYPE="1"><LI><FONT COLOR = "0000FF">Blue</FONT>: Text by me; &copy; Theo Todman, 2018</li><LI><FONT COLOR = "800080">Mauve</FONT>: Text by correspondent(s) or other author(s); &copy; the author(s)</li></OL> <BR><HR><BR><CENTER> <TABLE class = "Bridge" WIDTH=950> <TR><TD WIDTH="30%">&copy; Theo Todman, June 2007 - August 2018.</TD> <TD WIDTH="40%">Please address any comments on this page to <A HREF="mailto:theo@theotodman.com">theo@theotodman.com</A>.</TD> <TD WIDTH="30%">File output: <time datetime="2018-08-02T06:40" pubdate>02/08/2018 06:40:17</time> <br><A HREF="../../Notes/Notes_10/Notes_1010.htm">Website Maintenance Dashboard</A></TD></TR> <TD WIDTH="30%"><A HREF="#Top">Return to Top of this Page</A></TD> <TD WIDTH="40%"><A HREF="../../Notes/Notes_11/Notes_1140.htm">Return to Theo Todman's Philosophy Page</A></TD> <TD WIDTH="30%"><A HREF="../../index.htm">Return to Theo Todman's Home Page</A></TD> </TR></TABLE></CENTER><HR> </BODY> </HTML>