The Cats have won seven games this season by fewer than two goals and they came from behind to beat Carlton by six points at Etihad Stadium – the second time this season they have beaten the Blues by a goal or less in 2014.
Carlton led from the 11-minute mark of the third quarter until the dying minutes when Allen Christensen converted his set shot following a controversial free kick.
Caddy, who played a key role in the midfield, said the Cats' belief meant they never felt as though they were out of games.
"It's a combination of opposition sides knowing that we're just going to keep coming and almost expecting that we're just going to win," he said.
"I think we mentally have it over a few sides late in games and we've got some really good players that have just done that over their careers.
"There's games I've been involved in where we've been 20 or 30 points down in the last quarter and you still have this belief that you're a chance to get back and win.
"You don't necessarily always, but we just have that never-say-die attitude."
Caddy was arguably best on ground on Friday night, finishing with 28 possessions (16 contested), four inside 50s and a goal.
After missing two months with a foot injury earlier in the season he has been a regular substitute, but he said Friday night's game was a big step forward.
"I've had a bit of a frustrating year with injury and being the sub a couple of times since I've been back, but I felt as if I was in good form the last few weeks," he said.
"The challenge for me is to make that the benchmark and keep building."
Coach Chris Scott agreed and said it was more pleasing for the Geelong coaches to see the team's young players leading the way than their veterans.
"He (Caddy) and George Horlin-Smith have suffered a little bit because we've had some pretty well-performed players going through our midfield, so they've been starved of game time to an extent over the last month," Scott said.
"The positive of (Jimmy) Bartel, (Jordan) Murdoch and (Steve) Johnson going out is Caddy and Horlin-Smith got really good game time.
"I thought Caddy led us as much as anyone in the second half, particularly with the work in and around the ball."
