http://events.nationalgeographic.com/events/speakers/2010/02/10/third-man-factor

The February John Geiger program has been canceled, but will be rescheduled for the fall. Refunds will be made in the method in which the tickets were purchased. Ticket holders who paid via credit card will receive an automatic refund on their credit card. Ticket holders who paid via check or cash should send their name and address, along with their ticket, in order to get the refund.

http://www.scientificamerican.com/article.cfm?id=the-sensed-presence-effect

In the 1922 poem The Waste Land, T. S. Eliot writes, cryptically: Who is the third who always walks 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.