I Do Know What You Think I Think: Second-Order Theory Of Mind In Strategic Games Is Not That Difficult

I Do Know What You Think I Think: Second-Order Theory Of Mind In Strategic Games Is Not That Difficult Ben Meijering 1 (b.meijering@rug.nl), Hedderik van Rijn 2 , Niels A. Taatgen 1 , & Rineke Verbrugge 1 Department of Artificial Intelligence, University of Groningen, and 2 Department of Psychology, University of Groningen Abstract This paper is about higher-order theory of mind such as “I think that you think that I think …”. Previous studies have argued that using higher-order theory of mind in the context of strategic games is difficult and cognitively demanding. In contrast, we claim that performance depends on task properties such as instruction, training, and procedure of asking for social reasoning. In an experiment based on a two- player game, we manipulated these task properties and found that higher-order theory of mind improved by providing step- by-step instruction and training. It also improved during the experiment when participants were explicitly asked to predict the opponent’s next move. Keywords: Theory of Mind; Social Cognition; Higher-Order Social Reasoning; Strategic Games. Theory of Mind Whenever the outcomes of our actions depend on the decision of others, and vice versa, we need to reason about one another. For example, if a researcher wants her paper to be accepted, she not only needs to have interesting empirical results, she also needs to get her story across. She needs to reason about what an intended reader knows beforehand and about what he will infer from reading her story. She may even wonder whether a particular reviewer knows that she knows that he was the one who wrote that glowing review. The ability to reason about the knowledge, beliefs, desires and intentions of others, in this case the reader, is often referred to as Theory of Mind (Onishi & Baillargeon, 2005; Wimmer & Perner, 1983; Premack & Woodruff, 1978). So far, empirical findings have shown theory of mind to be far from optimal, especially in more complex social interactions (Flobbe, Verbrugge, Hendriks, & Kramer, 2008; Keysar, Lin, & Barr, 2003; Hedden & Zhang, 2002; McKelvey & Palfrey, 1992; but see Goodie, Doshi, & Young, 2010). The conclusion often drawn from these findings is that theory of mind is difficult and cognitively demanding (e.g., Verbrugge & Mol, 2008). In contrast, we claim that performance depends on the task. For example, participants seemed to have little difficulties applying theory of mind in false-belief story tasks (Flobbe, et al., 2008). We claim that suboptimal performance due to task difficulties can be overcome by providing appropriate instruction and training. Social reasoning involves interplay of multiple serial and concurrent cognitive processes, and learning to apply theory of mind in a particular task might benefit from instruction and training that structure this interplay of processes. Besides instruction and training, the procedure of asking for social reasoning can also contribute to providing a supporting structure, so-called scaffolding, for the interplay of processes that underlie social reasoning. In the current study, we show that providing supporting structure that maps with the reasoning steps required by the task facilitates social reasoning and improves performance. Orders of Reasoning Complex social interactions such as rescue operations and negotiations are cognitively demanding because of the depth, or order, of reasoning they require (Verbrugge, 2009). To illustrate orders of reasoning, imagine a social interaction between Ann, Bob, and Carol, and that Bob’s birthday is tomorrow. Furthermore, Ann knows: “Bob’s birthday is tomorrow”. This is an example of zeroth-order or non-social reasoning, because Ann is not yet reasoning about someone else’s mental state. She merely recalls a fact. If Bob thinks: “Ann knows my birthday is tomorrow”, he is applying first-order reasoning, because he ascribes knowledge to Ann. First-order reasoning covers a great deal of social interactions. Another example of a first-order attribution is Bob’s thought: “Ann intends to throw me a surprise party, because she always throws surprise parties”. In this example Bob ascribes an intention to Ann. A social interaction between Ann, Bob, and Carol may demand reasoning of one order deeper: Suppose that Ann will not throw Bob a surprise party and expressed this to Carol. Now, Carol knows that “Bob falsely believes that Ann intends to throw him a surprise party”. Carol applied second-order reasoning, which is a complex skill that starts developing around the age of 6 to 9 years and apparently remains challenging throughout the later lifespan (Perner & Wimmer, 1985). Second-order reasoning is the main focus of the current study. Hedden and Zhang’s Experiments So far, most studies showed suboptimal application of second-order theory of mind in social interactions that involved the perspective of a participant and one other player (Flobbe, et al., 2009; Hedden & Zhang, 2002; McKelvey & Palfrey, 1992). For example, McKelvey and Palfrey (1992) presented participants with games in which they had to reason about an opponent’s decisions. Participants’ behavior in these games was not optimal. Also, Hedden and Zhang (2002) presented participants with so- called matrix games in which they had to apply second- order theory of mind. Performance started at approximately 25% and gradually increased to approximately 65%. Figure 1 depicts examples of matrix games, which are two-player sequential-move games. Each cell of a matrix