The presence of discourse relations can be marked explicitly with lexical items such as specialized and underspecified connectives or left implicit. It is now well established that the presence of specialized connective facilitates the processing of these relations. The question is to gauge how different degrees of explicitness affect the processing of discourse relations. This study investigates this question with respect to two relations, which are fundamental to our cognition and which are closely tied: causal relations and temporal relations. We (...) carried out a self-paced reading experiment, in which we sought to compare the cost of inferring the presence of causal vs. temporal relations in the absence vs. presence of a connective indicating a given relation in French. For the explicit marking, two types of connectives were tested – one specialized for each relation (doncfor causality andpuisfor temporality) and one underspecified (etin its temporal and causal readings). Overall, our results confirm the facilitator role of discourse connectives: we find that explicit discourse relations are processed faster than implicit ones. The specific (rather than underspecified) connective facilitates processing for temporal relations but not for causal relations; and temporal relations were read equally fast as causal relations. (shrink)