Coherence relations and their linguistic markers play a significant role in the study of discourse processing and comprehension. A number of studies have shown that the presence of coherence markers, such as connectives, in a text facilitates discourse processing and representation. The current study focuses on causal connectives, and investigates how the information that is encoded in their processing instructions affects online discourse processing. More specifically, it investigates whether these connectives provide cues about the fine-grained distinction between subjective and objective causal relations. This question is relevant for two reasons. First, in many languages of the world causal connectives seem to specialize in either subjective or objective causal relations. And second, subjective causal relations are assumed to be more complex than objective causal relations. In order to investigate this issue, this study includes a series of eye-tracking experiments involving both backward (want versus omdat) and forward (dus versus daarom) Dutch causal connectives. The results reveal that causal connectives do more than just inform the reader that a causal coherence relation needs to be constructed between two pieces of text. They also provide information about the relative degree of subjectivity of that causal relation, which immediately affects online discourse processing. In addition, the results shed a new light on the source of the processing complexity of subjective causal relations.