It has been said that the feet are the most honest part of the body when reading others. Millions of years ago, we gave up quadrupedalism to walk upright leaving our feet to the dirt. While our hands busied themselves with other complex and conscious tasks like fire building, making clothing and shelters, throwing spears, our legs were relegated to more primitive activities like locomotion which is generally carried out subconsciously. The hands, because of their opposable thumbs, are more useful to complex tasks, putting the thinking neocortex in charge. This in turn hampers honest language in the hands and arms because the thinking mind can, within reason, eliminate the type of body language it desires.
The feet on the other hand, carried out more traditional tasks like escaping predators, avoiding hot sand or coals from the fire, leaping from slithering snakes or poisonous spiders, or navigating rough rocking river bottoms. The feet were therefore connected more to the reptilian brain which reacts to stimuli directly instead of contemplating higher order tasks that require planning. When we’re frightened it doesn’t take much to put our feet in gear by getting them tucked under our legs and coiled up, or freezing instantly, or pulling them up onto a chair when startled by a mouse that catches our eye as it scampers across the shadows of a room.
Where people point their feet indicates their intent. If feet are pointed to a doorway, we know that someone wants to leave. People will point their feet to the person they want to talk with, even if they are already talking with someone else. If feet are tucked in, under a chair and crossed, they are withdrawing but not leaving. If feet are crossed at the ankles, a person isn’t leaving any time soon, but they might harbour some negative thoughts. If feet are apart, the person is open and confident.