I've watched the first few episodes after not having seen it in over 20 years and it seems to me that they're pretty much interchangeable. I seemed to remember each of them having just enough personality ticks to make them distinguishable from one another.
Do these begin to emerge as the series goes along?
’Cause there’s thunder in your heart... Every move is like lightning!
Watch "The Duck in the Iron Mask". It deals with this very subject. It's also the only episode from the first season that I can think of that reveals distinquishing personality traits. I say the first season because I never watched much of the second season.
shareThe real distinguishable personality traits didnt come along until the spinoff series Quack Pack. On that show Huey was more or less the leader fo the three, Dewey was the smart one and Louie was into sports.
"You win some, you lose some. But you live, you live to fight another day."
I think they do differ a bit.
shareI think the colours of their clothing define their personalities (At least symbolically).
Huey (Red) - proactive albeit slightly temperamental
Dewey (Blue) - calm and placid but intelligent from an academic perspective
Louie (Green) - optimistic and cheerful with a talent for physical action
Think of it this way: Huey is Kirk, Dewey is Spock, Louie is McCoy.