It is often the case that complex traits such as intelligence are very hard to define. But it is also true that there are “proxy” signs that we can all pick up on. One recurring sign of intelligence for me is “intentionality”. I’ve found in my experience that intelligent people are highly intentional. Look at the minute design decisions made by business greats such as Steve Jobs. They leave nothing ambiguous. They demand high standards. There is no “whatever” in an intelligent’s person vocabulary. Intelligent, focused individuals know that whatever decision one doesn’t make will get made for them. And so, they are decisive!