Three basic operations for the analysis of argumentative practice are distinguished: affirming, justifying, and criticizing (objecting). These are explained and illustrated in detail, and figures of justifications and objections (fallacies) are examined. A discussion of the completeness of this system of three operations shows that any other operation in argumentation can be reduced to them and that the three operations are necessary for a proper model of argumentative practice (i.e. that both fallibilism and justificationism are insufficient, the former disregarding justification and the latter criticism).