"Allow me to offer a little image to illustrate this. We find, in nature, two different kinds of skeletons that provide structure for creatures - the exoskeleton and the endoskeleton. The exoskeleton like the carapace of an ant or a beetle - it is on the outside (hence "exo-") and contains within itself the essence of the creature. The endoskeleton is like the skeleton of a dog or a man - it is on the inside (hence - "endo") and the structures that are the essence of the creature are hung upon it - everything in its place and a place for everything.-- Archpriest David Moser, from the Orthodox-Convert e-mail discussion list
The Western confessions tend to have a dogmatic endoskeleton - certain a-priori assumptions (dogmas) upon which every doctrine, belief and practice is hung. There is a very particular place for everything in the overall organization and structure and if something is out of place then it either doesn't belong or it creates chaos.
The Orthodox Faith tends more towards a dogmatic exoskeleton - defining the outer limits of its essence, but not mandating the inner structure. Everything that is "inside" is part of the teaching of the Church and only those things that are "outside" are excluded. As a result there plenty of room for doctrines and practices that are conflicting to coexist "inside" the Church without causing chaos or cancelling each other out. Our inner unity is defined by the exoskeleton of dogmatic pronouncements without the rigid and defined structure mandated by an endoskeleton (and this allows the Orthodox Church to be both truly One and truly Catholic since it allows the flexibility to address all people in all places in all times without compromising or breaking the structure.)"