"Superstitious beliefs" refers to irrational or unfounded beliefs that certain actions or objects have the ability to bring good or bad luck, without any scientific or logical evidence to support it. Full definition
Black cats (or dogs) can be are more difficult to see in a cage, particularly if the lighting isn't great and some people have superstitious beliefs about black animals. (petliferadio.com)
This charge of atheism led the heathens to their unconquerable superstitious beliefs. (religion-online.org)
More than anything, Paul was a profound humanist with a keen awareness of the harmful power of certain superstitious beliefs, so much so that he founded and became the first Chair of Family Action Information and Rescue, an anti-cult organisation. (politics.co.uk)