I'm currently thinking about starting to expand my knowledge of logic beyond what I retain from my previous study of logic by making use of the materials available through: OpenLogicProject
I have read that it requires that I read at least a 'beginners' book on logic; therefore, I have started with Paul Teller's a Modern Formal Logic Primer.
Is the OpenLogicProject ("OLP") something I can progressively learn from without nail-biting and ear-pulling, having only read and completed a primer on modern formal logic? Has anyone else completed the entire document of the OLP and if so, did it provide the necessary depth to tackle more 'advanced' topics in logic? Also, does the majority of the material in OLP cover 'Philosophy of Logic', or 'Mathematical Logic'?