tl;dr I think your critique i justified. The lack of a common methodology, terminology, and subject matter prevents clearly discernible, continuous progress in

tl;dr I think your critique i justified. The lack of a common methodology, terminology, and subject matter prevents clearly discernible, continuous progress in philosophy. Long answer: First, although there has been progress in philosophy, it is much slower than in the natural sciences and harder to discern. Second, unlike any other discipline, philosophy has no agreed upon methodology and no agreed upon subject matter. A consequence of both of these properties of philosophy is that older works can stay relevant and transformations and interpretations of them are often contested. It is very common for secondary literature to re-interpret heavily and in ways that might not capture the original author's intentions. Since work in philosophy is primarily working with texts, this explains the heavy focus on primary literature. Since there is plenty of progress in philosophy, however, just reading the primary sources mentioned above would not get you anywhere. As a rule of thumb, the older a book or article, the more you'll have to take into account their reception. Otherwise you won't philosophize at a contemporary level and won't be able to publish about the work. For instance, writing anything insightful about Kant's Critique of the Pure Reason or Plato's Politeia will require specialization and taking into account many previous interpretations. Some people would dismiss philosophy entirely because it has no common subject matter and widely accepted methodology, except for having relatively high standards for working with texts that are similar to those of historians and fairly high standards for laying out arguments. That's fair enough, but kind of short-sighted. Philosophy has had a tremendous influence on the sciences and still occasionally has. Basically, philosophy is all about reading texts and unfortunately this often gets in the way of actually "philosophizing." I've met many philosophers who got lost in texts and never returned - they end up doing history of philosophy. My best advise to anyone interested in philosophy is to approach it the way I was taught in Tübingen 30 years ago. Approach original texts seriously and in-depth, but carefully choose those texts and only read what interests you. There is no need to read the Critique of the Pure Reason if you're interested in contemporary analytic "accuracy first" epistemology, for example.