The video presents some intuitions behind the most basic concepts in mathematics. The research of human expressions suggests that humans tend to think in two distinct ways which could be combined in various manners. The theory can be applied to various fields one of which is mathematics. The ideas in this video come from a book published in 2014 under a title CONCEPTUAL UNDERSTRUCTURE OF HUMAN EXPERIENCE which could be purchased from AMAZON. The research of human expressions suggests that many concepts in mathematics and elsewhere can be interpreted as either - a value or extent of value - intensity or extent of intensity - magnitude or multitude - nesting or repetition - state or process - bounded or unbounded - and so on. I discuss this inherent duality by using walking as an example.