Why do we say “open” and “closed”? Why is one in present tense and the other in past tense?

Question

Edit: to clarify, I mean when shops have a sign that says “open” versus “closed”. Why is it not “opened/closed” or “open/close”?

In: Other

Answer 1

A theory – it removes the ambiguity between “close” (near) and “close” (to shut).

If we used “open” and “close” to specify the status of being open or not, in written English, we’d create ambiguity between a nearby door and a shut door. By using “closed”, we remove that ambiguity.

Also, in the other direction, there is a distinction between “the store was open” (was open at the time) and “the store was opened” (opening for the day, or perhaps for the very first time). The latter is rarely used but does have a slightly different meaning.