The article doesn’t though. East is a path parallel to the equator on a spheroid. East of Seattle is a circle around the globe at a particular latitude. Facing the thing 1mm east of Seattle is a different heading than facing the thing 5000km east of Seattle.
As has already been said as soon as you “go”, if you aren’t turning some infinitesimal amount you aren’t going east. It’s only a surprising result when misleading people by arguing that east is a particular heading.
But it just said in a straight line to the east. It gave you a cardinal direction to start. From there forward, you go in a straight line.
It gets tricky if you suggest that you can only travel along a great circle in the direction of the rotation along that axis. Since the axis is actually tilted, this is the result you get from traveling along that great circle.
The issue people have is with "straight". It's ambiguous. And the simplest, most intuitive interpretation of "straight" in the context of someone directing you to travel East, is to continue travelling East.
It's like handing someone a compass pointing East, then saying "walk in a straight line", and expecting them to slowly travel in a wandering arc. It's insane.
Maybe so, but that's not how geometry works. If geometry worked by my interpretation, then I would have skated through that class with an even higher grade than I got by following the rules.
Also, the GGGGP that I replied to started by trying to walking a tangential line to a sphere resulting in a space walk. That's like THC induced levels of strained thinking of the subject.
Really? The title of the puzzle isn't part of the puzzle?
Then the first line of the puzzle should be "completely ignore the title of this puzzle because it's somehow not part of the puzzle. It's unrelated. It will completely mislead you"...
If you have a problem with the title, then take it up with the submitter. The title of the TFA is "A path from Seattle". The article just says to walk in a straight line while facing due east. It does not say to travel East. I know I sometimes have an issue of reading over things too quickly to actually comprehend properly. Maybe this happened to you too?