<div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif;background-color:transparent">On Mon, Jul 13, 2026 at 6:42 PM Brent Allsop via extropy-chat <<a href="mailto:extropy-chat@lists.extropy.org">extropy-chat@lists.extropy.org</a>> wrote:</span></div></div><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr"><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><font size="4" face="georgia, serif"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>First off, what happens in the retina is causally far upstream from the rendered subjective experience,</i></font></div></div></blockquote><div><br></div><div><font size="4" face="tahoma, sans-serif"><b>The retina is considered to be part of the brain<span class="gmail_default" style=""> because they both contain the same sort of cells and </span><span class="gmail_default" style="">they both developed from the </span><span style="background-color:transparent">embryonic forebrain<span class="gmail_default" style="">; it's not just a light sensing organ, it performs extensive visual processing. The retina is especially interesting because it is the only part of a living brain that can be accessed without opening the skull. </span></span></b></font></div><div><br></div><div><a href="https://brain.harvard.edu/hbi_news/the-eyes-have-it/"><font size="4" face="tahoma, sans-serif"><b>Harvard brain science initiative</b></font></a><br></div><div><br></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font size="4" face="georgia, serif"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>Tetrachromat humans are mostly female,</i></font></blockquote><div><br></div><div><font size="4" face="tahoma, sans-serif"><b>That's because the gene for it is rare<span class="gmail_default" style="">, you need 2 of them, and it's on the X chromosome, and women have 2 X chromosomes but men, being XY, only have one.</span></b></font></div><font face="arial, helvetica, sans-serif"><br></font><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><font size="4" face="georgia, serif"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>I guess it is possible this is all purely 'functional', but either way, whatever is responsible for this 4th quality would surely be objectively observable and distinguishable from the other qualities, right?  And IF there is some 'function' from which redness 'arises,' that would still be a, what John refers to as a "brute physical fact," right?</i></font></div></div></blockquote><div><br></div><div><font size="4" face="tahoma, sans-serif"><b>Maybe maybe not.<span class="gmail_default" style=""> A t</span><span style="background-color:transparent">etrachromat<span class="gmail_default" style=""> Human can objectively detect more </span></span><span style="background-color:transparent">subtle differences between hues, shades, and gradations tha<span class="gmail_default" style="">n</span> normal trichromat<span class="gmail_default" style="">s can, whether that means they can experience an entirely new color qualia I will never know. But as </span></span><span style="background-color:transparent">far as I know</span><span class="gmail_default" style="background-color:transparent"> </span><span style="background-color:transparent">Concetta Antico<span class="gmail_default" style=""> is t</span></span><span class="gmail_default" style="background-color:transparent">he only </span><span style="background-color:transparent">Tetrachromat<span class="gmail_default" style=""> who is also a professional artist and, for whatever it's worth, her paintings are certainly very colorful. </span></span><span style="background-color:transparent"><span class="gmail_default" style="">T</span></span><span style="background-color:transparent">ake a look at <span class="gmail_default">them on </span>Google image search<span class="gmail_default" style="">:</span></span></b></font></div><div><span style="background-color:transparent"><br></span></div><div><span style="background-color:transparent"><a href="https://www.google.com/search?q=Painting++%22Concetta+Antico%22&sca_esv=b3fbd9fc0a9dd966&as_st=y&udm=2&sxsrf=APpeQnvtrlLEQ_SchhB33PEBFCVv7Z0zbA:1784057392416&source=lnt&tbs=isz:l&sa=X&ved=2ahUKEwia1IjZ89KVAxXIjIkEHaCcKLIQpwV6BAgIEAY&biw=1463&bih=739&dpr=3.5"><font size="4" face="tahoma, sans-serif"><b>Concetta Antico</b></font></a><br></span></div><div><br></div><div><div class="gmail_default" style=""><font size="4" style="" face="tahoma, sans-serif"><b>John K Clark</b></font></div><br></div><div><span style="background-color:transparent"><br></span></div><div><span style="background-color:transparent"><br></span></div><div><span style="background-color:transparent"><br></span></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><br></div></div>
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