<div dir="ltr"><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Am Mi., 12. Feb. 2020 um 01:29 Uhr schrieb stevea <<a href="mailto:steveaOSM@softworkers.com">steveaOSM@softworkers.com</a>>:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Feb 11, 2020, at 3:45 PM, Mateusz Konieczny via talk <<a href="mailto:talk@openstreetmap.org" target="_blank">talk@openstreetmap.org</a>> wrote:<br>
> OTG is not "everything must be mapped on survey", it means<br>
> that direct survey (what is actually existing) overrides official data, opinions and desires.<br>
<br>
I thank Mateusz for making (reiterating?) this important point. </blockquote><div><br></div><div><br></div><div>+1</div><div><br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">I believe some of us think OTG is an absolute rule which states "map what is on the ground." Logically, we should be able to "derive" the potentially equivalent statement "if you canNOT see it on-the-ground, you may NOT (should not) map it." But that's not how we map, due to numerous counter-examples (some boundaries, mountain ranges, oceans...). </blockquote><div><br></div><div><br></div><div>I believe it is a misconception to think it must be "visible" on the ground, rather it must be determinable on the ground / "in loco". There might well be nothing to "see", but you could still check on the ground, by talking to the local people, how to map something (particularly, how to call it).</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">
Start with "If A, then B" where A is "it is on the ground" and B is "you may map it." Now, try the contrapositive "If not B, then not A" (in logic notation: ¬B -> ¬A). </blockquote><div><br></div><div><br></div><div>this is not how complex situations work. "If its black it is not colored" does not mean that if its not colored it must be black (could be white, gray, etc.).<br></div><div><br></div><div></div></div><div>Cheers</div><div>Martin<br></div></div>