Author’s note: This essay was originally published on February 1, 2026. Enjoy!
Emojis play an important role in today’s communication landscape. They include happy faces, sad faces, and angry faces; praying hands, hands with thumbs up, and hands with thumbs down; and not to be forgotten, eggplants, tacos, and poop. For most of human history, people had no need for emojis, but now they are ubiquitous in texts and emails. How come?
To answer this question, we need to reflect on the difference between spoken and written language. In spoken language, we can easily express emotion. Consider the word “really.” Depending on how we say it, the word can express certainty, but it can instead indicate skepticism. If we can see a speaker, we can also take their facial expression and body language into account in assessing the emotional content of their utterance—something impossible to do in written communication.
The advent of email and texting has dramatically decreased our dependence on in-person communication. We instead exchange typed messages in which it can be difficult for the reader to discern the intent of the writer. Was a comment meant as a joke, or was it an insult? This led one computer scientist to suggest, in 1982, that those using his department’s electronic bulletin board employ the characters :-) to indicate that they were joking. The idea caught on, and the emoticon was born.
In the late 1990s, emoticons were supplanted by emojis, at first in Japan and then globally. Rather than being “abstract pictures” constructed with ASCII characters the way emoticons were, emojis were tiny pictures, designed to be used in cell phone texting. These static emojis have subsequently been supplemented with animated emojis: In addition to the heart emoji, for example, there is the visibly-beating-heart emoji.
The advent of the graphical user interface (GUI) in the 1980s gave rise to icons, which performed a different function than emoticons or emojis. The latter could be sprinkled into an email or text to indicate the writer’s emotional state or intent. By way of contrast, icons were virtual buttons that, when pressed, made something happen, such as opening a file or launching an app.
Before 2009, Facebook users could add a thumbs-up emoji 👍 to a post. In that year, a thumbs-up icon (also known as a “Like button”) was introduced. Although the icon resembled the emoji, it had a different function. Clicking on the Like button incremented a counter that was publicly visible. Clicking on it also had an impact on the algorithm Facebook used to determine what content you and other users were exposed to.
This brings us to the icons that appear in Substack posts and notes. Here is what currently appears at the bottom of a Substack post:
The heart on the left is a heart icon, not a heart emoji. The other three icons allow you to comment on, restack, and share the post.
The appearance of the heart icon here seems arbitrary. Why use a heart icon rather than a thumbs-up icon? This would be useful if, although you didn’t love a post, you liked or at least approved of it. And why not add a thumbs-down icon with which to indicate that you disliked a post?
In response to these suggestions, the powers-that-be at Substack might argue that they have limited space to work with and that they want to maintain a positive vibe among users, which can be accomplished by forcing them to characterize their approval of a post as loving it rather than merely liking it, and by not allowing them to express their dislike of a post.
I realize that there isn’t a lot of available space for icons, but there is room for one more, and the icon in question would maintain a “positive vibe.” As an aspiring Thinker, I propose the addition of a “brain icon”:
People would click this icon when they found a post to be both thoughtful and thought-provoking. They would, in essence, be declaring that “It made me think.” The current Substack icon layout is Feeler friendly. It helps users find things that other people like. Thinkers are unimpressed by what people like, though. What interests them is posts that, by exposing them to new information and encouraging them to rethink their current beliefs, help them attain their mind-optimization goal.
Realize that it would be possible for a Thinker, after reading a post, to hit both the heart and brain icons. This would be the case if they enjoyed reading a thought-provoking post. In other cases, though, they might hit only the brain icon, for the simple reason that they did not like discovering that a long-held belief was in fact mistaken, or that they were in the grips of confirmation bias. Ouch! At the same time, however, they would understand that in the long run, the benefits of abandoning mistaken beliefs and overcoming confirmation bias would more than make up for this initial discomfort.
To the Substack powers-that-be: I would love it if you took my brain-button suggestion seriously. ❤❤❤
Need more food for thought? Click here for my past essays, listed by title. Want to listen to rather than read my essays? Click here for narrations of my essays on becoming a Thinker, and click here for narrations of my essays on “applied thinking.” Narrations of my essays on becoming a Thinker are also available on your favorite podcast app. To play them, open that app and search for “Thinking More and Better,” and add episodes to your playlist.
I would argue that a light bulb would be more in line with a provoking post (similar to LinkedIn). Several other platforms have done the same.
Wow. The heart on the left is a heart icon, not a heart emoji. that's what i love.