I recommend the totally reversed order. First, A Pattern Language - the concrete examples presented there are IMHO the most compelling. Then The Timeless Way of

I recommend the totally reversed order. First, A Pattern Language - the concrete examples presented there are IMHO the most compelling. Then The Timeless Way of Building since it actually builds upon "A Pattern Language". There are quite a lot of references to particular patterns there, so you minimize forward references this way. The Nature of Order series generalize even more, so I'd read them after that. They rather independent from the TWoB and APL but I believe the way from the concrete examples (APL) to the generalizations is a better one. Here it's rather a matter of preference than one of forward-dependency.