Ministers of religion are sometimes criticized for 'interfering' in politics - especially by politicians who would prefer not to have the ethics of their policies examined too closely. However, there is usually nothing wrong with a priest speaking about politics, provided everybody knows that she is speaking as a priest and not a politician. In just the same way, it is fine to listen to advice from a man in the pub about what could be wrong with your car, provided you know whether he is a mechanic or a market gardener.

This is an important issue in risk communication. Many studies have shown that experts cannot estimate risks any better than non-experts, except in a restricted number of cases in which the risk is very specifically related to the expertise of the expert. This means we can rely on the opinion of experts only when they speak about their narrow field of speciality. Otherwise, their opinion is worth much the same as anybody else's.

Non-Expert

So, what do we call someone who is not an expert? The most common term is layperson but this is about as clumsy as non-expert. And the word has other connotations, over and above the meaning of non-expert. Layperson is a recent gender-neutral version of layman, which originated in the Middle Ages as a term for someone who was not a clergyman. Because the clergy were the only really educated people in those days, the term layman carried a sense of being uneducated. It seems odd to call a rocket scientist a layperson when she is speaking about quilt-making. Even more strange to refer to a priest, speaking about politics, as a layperson.

I have thought for a long time about this intriguing linguistic challenge (and I've made several bizarre suggestions over the years). My current preference is impert. It looks like the opposite of expert, in the same way that implicit is the opposite of explicit. In its original Latin, implicit means 'folded in' while explicit means 'folded out'. The 'per' in expert refers to some kind of trial or testing period, as in the English word peril. An expert has been through a testing period and has come out of it with recognition of expertise. Thus, impert would refer to somebody who is 'in a trial', trying something in which she is not an expert. Impert also has a nice association with impertinent, which has a sense of 'meddling in what is beyond one's proper sphere'.

The word impert does not carry the baggage associated with layperson, which suggests uneducated non-clergy. The word impert applies to a specific area of expertise (or impertise) whereas layperson implies a general lack of knowledge or experience. A priest can be an expert in liturgy or theology, and an impert in politics, without suggesting any lack of intelligence or education. Of course, a priest might well be an expert in politics too, just as a market gardener could also be an expert mechanic. If we have a good name for it, perhaps people would be more ready to admit being an impert.

Ref: The Online Etymology Dictionary