CMV: Belief in anything supernatural cannot be rational

To start, here's a few definitions/clarifications:

• Supernatural is anything that falls outside of the natural, observable universe.

• To be rational, it must be supported by evidence or axiomatic logic.

• To be irrational, it must be contridicted by evidence or axiomatic logic.

• To be arational, it cannot be argued for or against with evidence or axiomatic logic given the nature of the belief.

• Supernatural does not mean religious, religious doctrine may include a belief in something supernatural, but not all supernatural beliefs are religious.

• I am not trying to make a value judgement about belief in the supernatural.

Given you need evidence for something to be rational and anything supernatural cannot be observed by it's very nature, given it falls outside of the natural, observable universe, belief (of lack of belief) in anything supernatural is arational and cannot be justified.

For example, let's say that there is a supernatural chair that is responsible for deciding when chairs break. From our perceptive within the natural universe, we cannot tell the difference between an supernatural being, such as this chair, intervening in our universe from a fundamental property of the universe we just don't understand yet. We can't tell if our chair broke because this supernatural chair exists or simply because of natural forces. Therefore, we cannot gather any evidence for anything supernatural and as a result, we cannot make a rational argument for the existance or lack thereof of anything supernatural.

It's an idea me and my friend developed (techinically we were arguing about the existance of an objective reality, but it maps really well on to this) and I want to see what holes could be poked in it.