In this commentary paper, we discuss what symmetrical and bidirectional reasoning might have brought to humans by overviewing a collection of papers contributed to the special feature “Symmetry” in this volume. Several authors noted that bidirectional reasoning is deeply related to the ability to make abductive inference, which in turn allows quick and efficient reasoning and decision making based on heuristics. We point out that quick and efficient inference using heuristics is the very characteristics of young children's early word and concept learning as well, and speculate that well known biases children show in early word and concept learning could be explained as a consequence of abductions children have quickly formed through short exposure to language. Thinking this way, disposition to make bidirectional inference could potentially serve as a crucial building block (i.e., the prerequisite) for the competence of language in humans rather than the other way around. All in all, the papers contributed to the special feature forcefully suggest that thinking based on heuristics rather than logic is hallmark of human intelligence rather than limitation, and the disposition to draw bidirectional inference plays a key role there.
