The Sensorium

'The reduction of the sensorium into five senses was first determined by aristotle, but galen said there were six, erasmus darwin thought there were twelve and von frey reduced them to eight. Zen buddhists say there is a sixth sense. Recent authorities calculate that there are seventeen senses.'
If you avoid the new age sixth sense BS I think you can reduce the senses to three - radiation interaction which would include sight and heat detection, physical interaction (which includes touch and hearing - hearing is just your ears physically interacting with the kinetic energy in the air) and chemical interaction (taste and smell which are one and the same in most respects anyway - the tastebuds and smelling things in your nose react to the chemicals in the air or what you put in your mouth).