Third Man factor

The Third Man factor or Third Man syndrome refers to the reported situations where an unseen presence such as a spirit provides comfort or support during traumatic experiences. Sir Ernest Shackleton in his book South, described his belief that an incorporeal being joined him and two others during the final leg of their journey. Shackleton wrote, "during that long and racking march of thirty-six hours over the unnamed mountains and glaciers of South Georgia, it seemed to me often that we were four, not three." His admission resulted in other survivors of extreme hardship coming forward and sharing similar experiences.

In recent years well-known adventurers like climber Reinhold Messner and polar explorers Peter Hillary and Ann Bancroft have reported the experience. One study of cases involving adventurers reported that the largest group involved climbers, with solo sailors and shipwreck survivors being the second most common group, followed by polar explorers. Some journalists have related this to the concept of a guardian angel or imaginary friend. Scientific explanations consider this a coping mechanism or an example of bicameralism. The concept was popularized by a book by John G. Geiger The Third Man Factor, that documents scores of examples.

Modern psychologists have used the 'third man factor' to treat victims of trauma. The 'cultivated inner character' lends imagined support and comfort.

Who is the third who walks always beside you?
When I count, there are only you and I together
But when I look ahead up the white road
There is always another one walking beside you
Gliding wrapt in a brown mantle, hooded
I do not know whether a man or a woman
— But who is that on the other side of you?

Lines 359 through 365 of T. S. Eliot's modernist poem The Waste Land (1922) were inspired by Shackleton's experience, as stated by the author in the notes included with the work.

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