Forms can be divided into causal and resultant forms and furthermore into fifteen:
- 1-4: the four causal forms, which are the four elements of earth, water, fire and wind.
- 5-9: the five sense objects of visual form, sound, smell, taste and texture.
- 10-14: the five sense faculties of eye, ear, nose, tongue and body.
- 15: the imperceptible form. This can further be subdivided into five: form of particles, spatial form, form resulting from a fully taken promise, imagined form and mastered form.
Forms 5-15 are said to be resultant forms.