In my article I present David Armstrong's stance on properties, relations, particulars and states of
affairs. I introduce this categories to show, at the most general level, his metaphysical system
called factualism. My article consists of four parts, in each one I characterize following categories:
1. Properties 2. Relation 3. Particulars 4. States of affairs. I also discuss Armstrong's arguments
considering the nature of those categories and their role in his philosophy. Also, I try to emphasis
differences between Armstrong's factualism and other contemporary metaphysical positions
(Bundle theory and Trop theory).