In times when a theory of history is already impossible, the only thing that can be theorized is the way of proceeding of historical discourse. Or the modes. Because we are not in the presence of a single historical discourse either. There are historian practices. Theorizing from singularities, then, has nothing to do with making theory from history from concrete cases. What it is about is to theorize each historian experience, to reflect on the theoretical and methodological operations put into play in the production of a historical situation. It is not a matter of theorizing each singularity, but the procedure put into play to build it: rescue the type of tools and the way they are used, transform a practical journey into theoretical experience. It is not a question, then, of practicing theories - that do nothing with their application, more than ideological weight - but of theorizing the practices in which we are involved. To jump from the opposition between empiricism and theoricism, let's say that it is not a matter of grounding a theory in a practice by deductive means: it is about reading the practices.