Friedrich Wilhelm Grafe<p><span class="h-card"><a href="https://mathstodon.xyz/@ereliuer_eteer" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>ereliuer_eteer</span></a></span> </p><p><span class="h-card"><a href="https://a.gup.pe/u/philosophy" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>philosophy</span></a></span> <br><span class="h-card"><a href="https://a.gup.pe/u/philosophie" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>philosophie</span></a></span> <br><a href="https://fediphilosophy.org/tags/philosophy" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>philosophy</span></a></p><p>It was @Kant suggesting that, where the <a href="https://fediphilosophy.org/tags/mathematician" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>mathematician</span></a> starts, <a href="https://fediphilosophy.org/tags/philosopher" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>philosopher</span></a> 's work is already done [Über die Deutlichkeit der Grundsätze... §1...] </p><p>Of course in a formal system, say <a href="https://fediphilosophy.org/tags/FOL" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>FOL</span></a>, <a href="https://fediphilosophy.org/tags/identity" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>identity</span></a> is simply the strictest equivalence relation, the unit classes of the domain being its equivalence classes. And yes, this is really elementary stuff, high school level, if you like. And no, that's not, why <a href="https://fediphilosophy.org/tags/philosophers" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>philosophers</span></a> at least since <a href="https://fediphilosophy.org/tags/Leibniz" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Leibniz</span></a> (and in a sense since <a href="https://fediphilosophy.org/tags/Parmenides" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Parmenides</span></a>), and more recently <a href="https://fediphilosophy.org/tags/Frege" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Frege</span></a> made a case for it. </p><p>Typically math philosophical issues with identity from my point of view do include the question of indiscernibles, the sense of an identity statement wrt. redundance, the relation status of identity, ... open list</p>