We often lack clear pro­ce­du­res for asses­sing state­ments and argu­ments advan­ced in ever­y­day con­ver­sa­ti­ons, poli­ti­cal cam­paigns, adver­ti­se­ments, and the other mul­ti­fa­rious uses to which ordi­na­ry lan­guage can be put. Cri­ti­cal thin­king is a method for eva­lua­ting argu­ments couch­ed in ordi­na­ry, non-for­mal lan­guage. Legal edu­ca­ti­on should fos­ter this argu­men­ta­ti­ve skill as an abili­ty to assess the open-end varie­ty of argu­ments that may ari­se in legal dis­pu­tes. I will argue that the abili­ty of cri­ti­cal thin­king helps lawy­ers to thri­ve even in legal cul­tures that are hosti­le to cri­ti­cal thin­king. The­re is, the­r­e­fo­re, a hap­py harm­o­ny bet­ween pro­fes­sio­nal and moral reasons to teach cri­ti­cal thin­king at law schools: it pro­mo­tes epis­te­mic as well as instru­men­tal rationality.