Telepathy is direct brain-to-brain contact. In x0 it is a poorly developed human sense somewhat like touch or smell but understood far less well. It is most often an emotional feeling received from someone else which is sometimes accompanied by a mental image, or sounds or words heard in one’s head including tunes or songs. It can also involve a physical sensation such as falling, nausea, or cold, or the memory of a smell, touch, or taste.

After I writing x0 I began to occasionally search for news about telepathy, and I noticed an increasing number of stories about using technology to achieve the same effect as psychic powers. In 2013 I described a story in Science about lab rats who had their brains wired together such that what one rat learned could be transmitted by direct wire to the other. Turns out that the other rat listened better if he got a treat for doing so (big surprise) but basically they communicated pretty well with what the researchers call a BTBI (brain to brain interface).

A couple of months ago Mark Zuckerberg made news by saying that the future of communication is telepathy. In a Q&A session with site users, he wrote “One day, I believe we’ll be able to send full rich thoughts to each other directly using technology. You’ll just be able to think of something and your friends will immediately be able to experience it too.”

The Washington Post responded with a well done article analyzing how this could work. They talked about the linked rats, as well as a University of California at Berkeley study in which a team of cognitive scientists managed to reconstruct clips of movies their subjects were watching, based solely on measurements of their brainwaves. They described how in another experiment involving a noninvasive technique called “transcranial magnetic stimulation” test subjects in India were able to think words to test subjects in France. The Washington Post added that “the process was painfully slow, however, and the words weren’t sent in their entirety — they had to be encoded as binary digits, uploaded to the Internet, sent, downloaded and then decoded as flashes of light.” Yes, painfully slow.

The article quoted Mark Harris at the MIT Technology Review as saying “‘Telepathy’ technology remains so crude that it’s unlikely to have any practical impact.” It concluded by noting that “even if Facebook isn’t leading the charge toward telepathy — a worrying concept in itself, given the site’s past indiscretions re: research consent and user privacy — the field poses tons of ethical challenges” which, lucky for us, “is many breakthroughs and advances away.”

Yes, it is. But it is worth remembering that most big advances began very slowly, at first, and their use and their impact were poorly understood. For decades, many people laughed at the idea of a fancy machine replacing something as reliable as a horse. We all know how that one worked out.