This article is from the RCA SelectaVision VideoDisc FAQ, by firstname.lastname@example.org (Tom Howe) with numerous contributions by others.
The answer to this question is an emphatic NO, but I'm surprised at the
number of people who have attempted this. It seems that people think the
CED disc will play, since it's about the same size and fits inside the
LaserDisc player. But the two systems are completely incompatible with
each other, so it likewise isn't possible to put a LaserDisc inside a
CED caddy and play it on a CED player. Attempting this will abrade the
surface of the LaserDisc, and probably get it stuck inside the CED