I was thinking about how one should express a lack
of belief in Christianity’s truth, in terms of the difference between
disbelief, unbelief and non-belief. I don’t know if my definitions accord with
yours - and please do say if you interpret your lack of belief differently to
this - but I take disbelief to be the firmest and most deliberate form of not
being a Christian, where a person with disbelief thinks Christian doctrines are
not true and responds with a kind of cognitive rejection. In other words, the
person has considered Christian teachings and rejects them.
I take unbelief and non-belief to be softer form of not being a Christian, and the distinction between the two is subtler than the distinction between either one of them and disbelief. I take unbelief to be a lack of belief, without specifying whether it's due to rejection, doubt, indifference, lack of exposure, and so forth. We can therefore think of unbelief as a broader term used to mean anyone who does not believe in Christianity’s truth, and non-belief as simply a purely descriptive distinction of lacking belief. So, in summary, as I see it, it’s roughly this:
Disbelief = “I believe Christianity is false.”
Unbelief = “I do not believe in Christianity’s truth” (but reasons vary).
Non-belief = “I lack the belief in Christianity’s truth” (pure description).
Consequently, the set of disbelief is contained within the set of unbelief, and both sets, disbelief and unbelief, are contained within the set non-belief. That is, the terms can be understood as nested sets: disbelief is a subset of unbelief, because anyone who rejects Christianity (disbelief) also lacks belief (unbelief), and both of these are subsets of non-belief, the broadest category describing anyone who simply does not hold Christian belief for any reason.
I have brought this consideration to bear on my editing of books I’m going to send to publishers, because I have been deliberating on the best term to use when describing non-Christians. It may vary in some contexts, but in broad application, non-belief/non-believer, therefore, appears to be the best option.
