Living in a highly individualistic culture, we might be tempted to believe we navigate the world as isolated rational actors guided solely by our own perception of reality. But as quantum physics can tell us, everything is connected to everything else -- and human psychology is no exception. One of the most fascinating studies of how emotional feedback from others shapes our own perception comes from psychologists Eleanor J. Gibson and R.D. Walk, who in 1960 devised a clever experiment dubbed the visual cliff study: The researchers placed 36 babies, one at a time, on a countertop, half solid plastic covered with a checkered cloth and half clear Plexiglas, on the other side of which was the baby's mother. To the baby crawling along the countertop, an abyss gapes open where the Plexiglas begins, signaling danger of falling, yet the solid feel of the surface offers ambiguous input. "Will I fall, or will I reach mom?," the baby ponders.

The researchers found that to make the assessment, the babies relied on the mothers' facial expression -- a reassuring, happy one meant they kept crawling, and an alarmed, angry one made them stop at the edge of the Plexiglas.

When faced with emotional ambiguity, most of us remain babies on Plexiglas -- we search for feedback to resolve uncertainty, and often forget that the Plexiglas is there, unflinching -- a solid, albeit invisible, support. We just have to take the leap... or crawl, as it were.

For more on the fascinating interplay between our cognition and the emotions of others, see the excellent A General Theory of Love, rereading which reminded me of the visual cliff study.

This post also appears on Brain Pickings, an Atlantic partner site.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.