The Scottish-born Australian philosopher John Anderson, whose Australian realism (aka Sydney realism) has greatly impacted on my overall philosophy and thinking, taught that a single logic applies to all things and how they are related, and that there are three---yes, three---‘entities’ to any relation such as seeing, having, knowing, etc, namely, the -er, the -ed, and the -ing. First, there is the person who sees, has or knows. Secondly, there is the thing seen, had or known. Thirdly, and most importantly, there is the act of seeing, having or knowing.