# Topology: Part II

We live in 3 Dimensional space with each dimension perpendicular to all the others.  The 1st Dimension is a Line.  In math this is the X axis.  When we add the 2nd Dimension (Y axis) we create a Plane.  When we add the 3rd Dimension (Z axis) we create Volume.

In 2D space we have three Primary Shapes: Square, Circle and Triangle (actually everything can be triangulated.)

In 3D space we have Geometric Primitives which relate in their formation back to the Primary Shapes through their starting shape and their translation (in this case translation means movement.)

Extruded Solids are any source shape that remains the same size as it translates.  Cubes, Cylinders and Prisms are examples of extruded solids.  A vertical section through each will result in a rectangle.

Converged Solids are any source shape which changes size as it translates.  Pyramids, Cones and Tetrahedron are examples of converged solids.  A vertical section through each will result in a triangle.

Revolved Solids are any source shape (square, circle or triangle) rotated (in the x, y & z axes) about one or more points.  Spheres* and Tori are examples of revolved solids.  A vertical section through a revolved solid will result in a circle.

Understanding these basic forms is the first step toward rebuilding for effect.

“Things we like from the past are because of their form not their content.”

– David Hockney**

* In math a sphere is in non Euclidean space while a Torus is in Euclidean space.

**If you’re interested in David Hockney please check out ‘David Hockney: A Bigger Picture’.