--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fig/ODandOrdinals.svg	Sat Jan 11 20:11:51 2020 +0900
@@ -0,0 +1,192 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xl="http://www.w3.org/1999/xlink" xmlns:dc="http://purl.org/dc/elements/1.1/" viewBox="68 87 578 643" width="578" height="643">
+  <defs>
+    <marker orient="auto" overflow="visible" markerUnits="strokeWidth" id="FilledArrow_Marker" stroke-linejoin="miter" stroke-miterlimit="10" viewBox="-5 -3 6 6" markerWidth="6" markerHeight="6" color="black">
+      <g>
+        <path d="M -3.7333333 0 L 0 1.4 L 0 -1.4 Z" fill="currentColor" stroke="currentColor" stroke-width="1"/>
+      </g>
+    </marker>
+    <font-face font-family="Helvetica Neue" font-size="22" panose-1="2 0 5 3 0 0 0 2 0 4" units-per-em="1000" underline-position="-100" underline-thickness="50" slope="0" x-height="517" cap-height="714" ascent="951.9958" descent="-212.99744" font-weight="400">
+      <font-face-src>
+        <font-face-name name="HelveticaNeue"/>
+      </font-face-src>
+    </font-face>
+    <marker orient="auto" overflow="visible" markerUnits="strokeWidth" id="FilledArrow_Marker_2" stroke-linejoin="miter" stroke-miterlimit="10" viewBox="-1 -3 6 6" markerWidth="6" markerHeight="6" color="black">
+      <g>
+        <path d="M 3.7333333 0 L 0 -1.4 L 0 1.4 Z" fill="currentColor" stroke="currentColor" stroke-width="1"/>
+      </g>
+    </marker>
+  </defs>
+  <metadata> Produced by OmniGraffle 7.12.1 
+    <dc:date>2019-11-28 04:44:00 +0000</dc:date>
+  </metadata>
+  <g id="Canvas_1" stroke-dasharray="none" stroke="none" fill="none" stroke-opacity="1" fill-opacity="1">
+    <title>Canvas 1</title>
+    <rect fill="white" x="68" y="87" width="578" height="643"/>
+    <g id="Canvas_1: Layer 1">
+      <title>Layer 1</title>
+      <g id="Graphic_6">
+        <path d="M 123 129 L 150.21835 251 L 177.4367 129 Z" fill="white"/>
+        <path d="M 123 129 L 150.21835 251 L 177.4367 129 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_7">
+        <path d="M 123 251 L 150.21835 373 L 177.4367 251 Z" fill="white"/>
+        <path d="M 123 251 L 150.21835 373 L 177.4367 251 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_8">
+        <path d="M 123 373 L 150.21835 495 L 177.4367 373 Z" fill="white"/>
+        <path d="M 123 373 L 150.21835 495 L 177.4367 373 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_9">
+        <path d="M 123 495 L 150.21835 617 L 177.4367 495 Z" fill="white"/>
+        <path d="M 123 495 L 150.21835 617 L 177.4367 495 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_10">
+        <ellipse cx="270.5" cy="478.5" rx="14.5000231695775" ry="82.5001318269064" fill="white"/>
+        <ellipse cx="270.5" cy="478.5" rx="14.5000231695775" ry="82.5001318269064" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_12">
+        <ellipse cx="293.5" cy="280.5" rx="14.5000231695775" ry="82.5001318269065" fill="white"/>
+        <ellipse cx="293.5" cy="280.5" rx="14.5000231695775" ry="82.5001318269065" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_13">
+        <circle cx="154.5" cy="181.5" r="6.50001038636232" fill="black"/>
+        <circle cx="154.5" cy="181.5" r="6.50001038636232" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_14">
+        <circle cx="154.5" cy="272.5" r="6.50001038636234" fill="black"/>
+        <circle cx="154.5" cy="272.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_15">
+        <circle cx="154.5" cy="304.5" r="6.50001038636234" fill="black"/>
+        <circle cx="154.5" cy="304.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_16">
+        <circle cx="154.5" cy="395.5" r="6.50001038636233" fill="black"/>
+        <circle cx="154.5" cy="395.5" r="6.50001038636233" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_18">
+        <circle cx="154.5" cy="424.5" r="6.50001038636234" fill="black"/>
+        <circle cx="154.5" cy="424.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_19">
+        <line x1="173.9379" y1="409.40815" x2="254.63666" y2="467.1495" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_20">
+        <line x1="176.16929" y1="434.5874" x2="254.55825" y2="471.07884" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_21">
+        <line x1="173.96816" y1="195.3658" x2="277.63543" y2="269.20077" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_22">
+        <line x1="178.3606" y1="273.87327" x2="277.5009" y2="279.5792" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_23">
+        <line x1="178.05217" y1="300.43344" x2="277.50804" y2="283.2612" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_24">
+        <circle cx="150.21835" cy="525.5" r="6.50001038636231" fill="black"/>
+        <circle cx="150.21835" cy="525.5" r="6.50001038636231" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_25">
+        <line x1="162.28478" y1="504.8674" x2="278.23874" y2="306.5955" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_26">
+        <text transform="translate(119.245 633)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="0" y="21">Ordinal</tspan>
+        </text>
+      </g>
+      <g id="Graphic_27">
+        <text transform="translate(224.256 584)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="10.989" y="21">Ordinal</tspan>
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="5968559e-19" y="47.616">Definable</tspan>
+        </text>
+      </g>
+      <g id="Graphic_47">
+        <path d="M 426 129 L 453.21835 251 L 480.4367 129 Z" fill="white"/>
+        <path d="M 426 129 L 453.21835 251 L 480.4367 129 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_46">
+        <path d="M 426 251 L 453.21835 373 L 480.4367 251 Z" fill="white"/>
+        <path d="M 426 251 L 453.21835 373 L 480.4367 251 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_45">
+        <path d="M 426 373 L 453.21835 495 L 480.4367 373 Z" fill="white"/>
+        <path d="M 426 373 L 453.21835 495 L 480.4367 373 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_44">
+        <path d="M 426 495 L 453.21835 617 L 480.4367 495 Z" fill="white"/>
+        <path d="M 426 495 L 453.21835 617 L 480.4367 495 Z" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_43">
+        <ellipse cx="573.5" cy="478.5" rx="14.5000231695775" ry="82.5001318269064" fill="white"/>
+        <ellipse cx="573.5" cy="478.5" rx="14.5000231695775" ry="82.5001318269064" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_42">
+        <ellipse cx="596.5" cy="280.5" rx="14.5000231695775" ry="82.5001318269065" fill="white"/>
+        <ellipse cx="596.5" cy="280.5" rx="14.5000231695775" ry="82.5001318269065" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_41">
+        <circle cx="457.5" cy="181.5" r="6.50001038636232" fill="black"/>
+        <circle cx="457.5" cy="181.5" r="6.50001038636232" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_40">
+        <circle cx="457.5" cy="272.5" r="6.50001038636234" fill="black"/>
+        <circle cx="457.5" cy="272.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_39">
+        <circle cx="457.5" cy="304.5" r="6.50001038636234" fill="black"/>
+        <circle cx="457.5" cy="304.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_38">
+        <circle cx="457.5" cy="395.5" r="6.50001038636232" fill="black"/>
+        <circle cx="457.5" cy="395.5" r="6.50001038636232" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_37">
+        <circle cx="457.5" cy="424.5" r="6.50001038636234" fill="black"/>
+        <circle cx="457.5" cy="424.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_31">
+        <circle cx="453.21835" cy="525.5" r="6.50001038636233" fill="black"/>
+        <circle cx="453.21835" cy="525.5" r="6.50001038636233" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_29">
+        <text transform="translate(422.245 633)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="0" y="21">Ordinal</tspan>
+        </text>
+      </g>
+      <g id="Graphic_28">
+        <text transform="translate(527.256 584)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="10.989" y="21">Ordinal</tspan>
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="5968559e-19" y="47.616">Definable</tspan>
+        </text>
+      </g>
+      <g id="Line_48">
+        <path d="M 604.7609 469.93216 C 612.0671 467.7524 618.9377 465.6045 624.34375 463.84375 C 637.5514 459.5421 639.2045 425.7619 633.77734 414.5703 C 628.35015 403.3787 602 397 574 385 C 546 373 545 374 507 358 C 469 342 416.78393 326.70416 398 311 C 379.21607 295.29584 381.79114 286.83255 383 279 C 384.20886 271.16745 393.904 266.09114 404 266 C 410.17797 265.94423 421.8459 265.70735 434.2442 267.17386" marker-end="url(#FilledArrow_Marker_2)" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_49">
+        <circle cx="453.21835" cy="149.5" r="6.50001038636234" fill="black"/>
+        <circle cx="453.21835" cy="149.5" r="6.50001038636234" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Line_50">
+        <path d="M 623.554 268.5201 C 625.4985 267.62867 627.6082 266.779 630 266 C 643.2077 261.69835 643.4272 246.1916 638 235 C 632.5728 223.8084 607 201 559 210 C 511 219 518.4367 243 480.4367 227 C 442.4367 211 413.62724 203.75242 394.8433 188.04826 C 376.0594 172.3441 378.63445 163.88081 379.8433 156.04826 C 381.05217 148.21571 390.7473 143.1394 400.8433 143.04826 C 408.3246 142.98073 423.85655 142.6476 438.987 145.39538" marker-end="url(#FilledArrow_Marker_2)" marker-start="url(#FilledArrow_Marker)" stroke="black" stroke-linecap="round" stroke-linejoin="round" stroke-width="3"/>
+      </g>
+      <g id="Graphic_52">
+        <text transform="translate(73.912 92.608)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="18474111e-20" y="21">OD contains Ordinals</tspan>
+        </text>
+      </g>
+      <g id="Graphic_53">
+        <text transform="translate(377.204 92.608)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="7105427e-19" y="21">OD has a name in Ordinals</tspan>
+        </text>
+      </g>
+      <g id="Graphic_54">
+        <text transform="translate(220 698)" fill="black">
+          <tspan font-family="Helvetica Neue" font-size="22" font-weight="400" fill="black" x="0" y="21">all arrows have to be acyclic</tspan>
+        </text>
+      </g>
+    </g>
+  </g>
+</svg>