if you add another switch it has two positions. one on and one off. how can you add two positions for one switch then only add one for the other? how i stated it is, is what my electrical teacher taught me years ago. he made have been wrong but i bought it. you always have one less switch than the circuit you are talking about. three switches and a load is a four way circuit. four switches and a load is a five way circuit. etc. the load i understand is a necessary part of the circuit. a two switch circuit is called a three way circuit, not a three way switch. the switch is called a three way switch in reference to the three way circuit. with no load, no circuit.