You know you’ve reached a crisis point in your email backlog when you’re obliged – as I was recently – to confront the following conundrum of electronic etiquette: is it ruder to reply to an email after three months than not to reply at all? On one hand, obviously, not replying is obnoxious. On the other, at least it lets the sender imagine that you missed their message entirely, or even that it never arrived; a reply implies, insultingly, that I had three months’ worth of more important things to do first (and/or that I’m hopelessly overwhelmed by emails – which is true, and particularly embarrassing, given that I’ve championed various systems for taming the monster in this very column).

In the end, I opted to reply. But even then I didn’t get closure on the matter, because of course the recipient didn’t say she was offended and, this being email, I had no facial expressions or vocal inflections by which to judge. The internet: helping us understand each other less well since 1969.

Three months is, let’s be clear, far too long to delay a reply. But I suspect we’re entering a phase in email’s history when social expectations about such matters have never been more in flux. As the burden of digital communication keeps increasing, “digital minimalism” is entering the mainstream. (I recommend a new book on the topic by the computer science professor Cal Newport.) Some of your email correspondents may be experimenting with radical cutbacks in their online time, while others are simply overwhelmed; some may have removed email from their smartphone years ago, while others run their whole lives from their inbox. Who’s to know what’s “normal” any more?

Recently, on the website The Cut, the psychology writer Melissa Dahl recalled her horror at learning that her social circle’s expectations for reply times to emails differed wildly from her own. She felt a week or two was often OK, but a colleague said she would be offended by that, while Dahl’s partner thought a reasonable timeframe was “probably within an hour”. I admire the fact that she even asked; I’m not sure I’d have the guts. That said, I can’t endorse her suggestion that we encourage others to set deadlines for their emails, so we would know when they required a reply, perhaps even sorting our inboxes according to their needs. I lack sufficient faith in humanity: there would be a huge incentive for people – especially those least entitled to my attention – to pretend their message was uniquely urgent.

I suggest we embrace the fracturing of consensus. The sense of uncertainty should help us see that, in reality, you’ve rarely got a clue why someone took so long to reply (or to do anything else, for that matter). Maybe they’re lazy. But maybe they’re moving house, or just had a baby, or are handling a family crisis, or are struggling with mental illness. It’s a self-serving argument, in my case, since I can plead only ordinary overwork, plus a winter of minor viruses caught from toddlers. But still the right approach, I think. “Be kind, for everyone you meet is fighting a hard battle,” in the words of a saying that’s almost as old as some of the contents of my inbox.

Listen to this

The academic and author Cal Newport explains how, and why, to live as a “digital minimalist” in an episode of the Hurry Slowly podcast

oliver.burkeman@theguardian.com