3D is not enough

The Electric part of the wave is energy of one directional time. The magnetic parts are the other 2 direction. 

Time it the hight, increasing from times below. Time grows. That's 2 out of 6. 

From the arrow of time, space is spread out in 4 direction. That's the full 6. 

Thinking of space as 3D is believing we're living in a triangular cone or something. 

All of this is in plain sight if you look at an EM-wave.