Health, Wealth & Wisdom

The Sixth Sense

July 17, 2006

“My skin is cold to the human touch… I don’t even hear when I think aloud” — Pink Floyd, Wearing the Inside Out

Before we get into health, let’s just get one topic out of the way: we are completely and utterly uneducated about the most fundamental aspects about how our bodies operate.

The degree of ignorance we continue to maintain in spite of the effectively infinite wisdom surrounding us is easy to sum up with our most common answer to the question: “How many senses do you have?”

Five. Right? I checked in May 2022 just to make sure kids aren’t any smarter these days than in the last century. We all have greater access to information, but we still don’t know any more that we did in the 20th century—not about our senses, anyway.

If you also answer “five” and then list seeing, hearing, touch, taste and smell, you’re in good company. However, this answer is vastly mistaken.

Doesn’t your sense of gravity count as a sixth? How do you know which way is up?

As of May 2022, the Wikipedia Sense page offers all the details for anyone who cares to explore further. The short story is that we now have a taxonomy of human and non-human sensations, and among those categorized as human, we organize them as general, external and internal.

The “general” set captures the familiar five, plus the one I proposed in 2006: vestibular sense.

Of the “internal” set, another one I hinted about in my 2006 blog post was proprioception, also known as kinesthetic sense. Try walking on ice, and notice what you “feel”—it certainly isn’t touch—and, yet, somehow, you know that you’re on ice and not asphalt or sand. That’s your kinesthetic sense at work in one of many of its capacities.

There are also cases of humans who use echolocation to make up for the lack of sight. There is a small group that reports extreme sensitivity to electromagnetic fields, qualifying them as having electroreception. And, it may not be long before human magnetoception is documented.

The page currently classifies hygroreception as a non-human sense, but anyone who is bothered by humidity might conclude that classification is absolutely absurd—after scratching their head for a bit, most would agree that hygroreception is yet another human sense.

Suffice it to say, we have a lot to learn, and in spite of decades of rapidly advancing access to knowledge, most of us can’t keep up.