Several philosophers maintain that outright belief exists because it plays a reasoning simplifying role (Holton 2008; Ross and Schroeder 2014; Staffel 2019; Weisberg 2020). This claim has been recently contested, on the grounds that credences also can simplify reasoning (Dinges 2021). This paper takes a step back and asks: what features of an attitude explain its alleged ability to simplify reasoning? The paper contrasts two explanations, one in terms of dispositions and the other in terms of representation, arguing in favour of the latter and against the former. The proposed explanation yields two interesting results: first, both belief and other attitudes, such as acceptance and imagination, can play a reasoning simplifying role; second, credences do not simplify our reasoning.