Is testability falsifiability?

Introduction Those who know the work of Karl Popper will have recognized in my title the transformation into interrogation of a formula repeated several times by this eminent philosopher of science, whom some consider as the greatest of the 20th century in his specific field even if they do not share his theses. This Popperian formula, to which I wish to devote my analyzes here, has at least the merit of being clear and impactful. But as often, what is clear and impactful can become too simple for what is to be thought, and perhaps even too simple to express faithfully the philosophy which one seeks to summarize there. Writing this, I am not claiming that Popper was not really a falsificationist. Far be it from me to dispute that the great thesis of his epistemology consists in making any scientific theory worthy of the name falsifiable or refutable. This is indisputable: for Popper, the dividing line between scientific theory and non-scientific theory lies precisely in this falsifiable character. That is why psychoanalysis, for example, is not for him a science: it