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Description: When asking if lightning caused the forest fire, one might think that the lightning is more of a cause than the dry climate (i.e., it is a graded cause) or they might instead think that the lightning strike completely caused the fire while the dry conditions did not cause it at all (i.e., it is a binary cause). Psychologists and philosophers have long debated whether such judgments are graded. To address this debate, we started by reanalyzing data from four recent studies. In this context, we provide novel evidence that causal judgments are actually multimodal: although most causal judgements were binary, there was also some gradation. We then tested two competing explanations for the gradation we observed: the confidence explanation, which states that gradation distinguishes between certain and uncertain causes, and the strength explanation, which states that gradation distinguishes between strong and weak causes. Experiment 1 tested the confidence explanation and showed that gradation in causal judgments was moderated by confidence. People tended to make graded causal judgments when they were less confident, but they tended to make discrete causal judgments when they were more confident. Experiment 2 tested the causal strength explanation and showed that although causal judgments varied with factors associated with causal strength, confidence ratings were unchanged. Overall, we found that causal judgments are multimodal and that observed gradation reflects independent effects of confidence and causal strength on causal judgments.