Design and Procedure
The procedure of our study is largely adopted from Noyes and Keil (2020) with a few small changes. We plan to use a 2 (properties/content: cultural vs. biological) by 2 (language form: generic vs. specific), fully-crossed, between-subject design. In addition to the two generic statement conditions from Noyes & Keil (2020), we will also include specific language conditions for each property/content condition. In the absence of previous research on the role of generics in the development of essentialist beliefs in Iran, it is important to explore how generics as a linguistic form and independent of their content may elicit essentialist beliefs in this context. These additional specific conditions enable us to determine a baseline for essentialist beliefs about novel social categories through development, and help us rule out the role of repetition11In Noyes and Keil (2020), the control and experimental trials differ with respect to how many times children have heard the relevant scenarios (they only hear the control trial once while they hear the experimental trial 16 times); in our design, we eliminate this difference between the control and experimental conditions..
All children will be tested in person and in Persian. At the start of the study, parents and children (and adult participants) will provide informed consent to participate. In a warm-up phase, they will first be introduced to and familiarized with a novel social category, the Foolies, and the island they live on. Then, in the teaching phase, they will be presented with one story book consisting of 16 sentences about the Foolies, based on the condition they were assigned to. In the specific conditions, the Foolies will be described in specific language and in the generic conditions, “Foolies” will be described in generic language (see stimuli below for more details). Two memory check questions will be included between the sentences in the teaching phase. For example, in the biological condition, participants hear the statement “Foolies have super strong finger nails.” and after a couple of more statements, they are asked “Do Foolies have weak fingernails, or super strong finger nails?”
For adults, the design will be identical, but they will be tested online. We will use Porsline, an Iranian online survey service (https://porsline.ir) to program the study for adults.