One prediction a lot of science fiction authors got wrong is the idea that all calls would some day become video calls. Today, the ability to make video calls is readily available, and yet a very small percentage of day to day conversations actually utilize video. Instead consumers have gone the other way entirely: rather than increase the resolution of our casual phone calls by adding images, we have opted for an even lower resolution form of communication—namely, texting.

As it turns out, there is an issue much more important than resolution when it comes to interface design. And that issue is the ability to multitask. Video calls demand your whole attention; not only do you have to appear as if you are listening, but you also have to worry about whether or not your physical appearance is up to par. One science fiction author, David Foster Wallace, got this pretty much exactly right in his classic novel Infinite Jest:

“[Video] callers now found they had to compose the same sort of earnest, slightly overintense listener’s expression they had to compose for in-person exchanges. Those callers who out of unconscious habit succumbed to fuguelike doodling or pants-crease-adjustment now came off looking rude, absentminded, or childishly self- absorbed. Callers who even more unconsciously blemish-scanned or nostril-explored looked up to find horrified expressions on the video-faces at the other end. All of which resulted in videophonic stress…

“And the videophonic stress was even worse if you were at all vain. I.e. if you worried at all about how you looked. As in to other people. Which all kidding aside who doesn’t. Good old aural telephone calls could be fielded without makeup, toupee, surgical prostheses, etc. Even without clothes, if that sort of thing rattled your saber. But for the image-conscious, there was of course no such answer-as-you-are informality about visual-video telephone calls, which consumers began to see were less like having the good old phone ring than having the doorbell ring and having to throw on clothes and attach prostheses and do hair- checks in the foyer mirror before answering the door.” (full excerpt)

Applying these same principles, it’s not hard to see why texting has become so popular. In contrast with phone calls, texting alleviates two additional causes of social stress—you no longer have to control your tone of voice, and you no longer have to answer in realtime. This frees up valuable attention for other tasks. Put simply, when it comes to multitasking:

texting > voice calls > video calls

Thus looking forward, we should expect the continued dominance of interfaces that minimize your need to pay attention while maximizing your ability to multitask. For this reason I am somewhat skeptical about whether or not voice activation, another science fiction favorite, will ever catch on as a dominant way of controlling our devices. In many scenarios, particularly when other people are present, voice activation is a liability that impairs rather than impedes multitasking. For example, using a standard cellphone swiping interface, it is extremely easy to look up the definition of a word, skim an email, or check your calendar while simultaneously and seamlessly carrying on a conversation with the person across the table. No such multitasking is possible with voice activation.

There are of course situations where voice activation is a net benefit, such as while driving. But if cars start driving themselves, then this special case vanishes rather quickly.

I have even more doubts about virtual assistants. Many futurists have envisioned anthropomorphic digital secretaries, often with custom personalities, whom we are supposed to converse with as if they are real people. It seems that in order to maximize efficiency and minimize social stress, the last thing I would want to do is put an artificially intelligent middle man between me and my computer.