472 International Organization incomes for those who own factors with which the economy is relatively well endowed (that is,labor skills in the developed economies),while disadvantaging owners of other factors (unskilled or low-skilled labor).?Scheve and Slaughter highlight as a"key finding"of their study the conclusion that "the preferences about trade and immigration policy align strongly with labor market skills."8 Mayda and Rodrik report that the results from their analysis of the importance of educational attainment in shaping views about trade are "strikingly supportive of the implications of the factor-endowments model and of the Stolper-Samuelson theorem."9 Yet there are other,plausible,ways to interpret the positive relationship between the education levels of surveyed individuals and their support for trade openness. It seems particularly limiting to consider education only as a measure of workers' skill levels,relevant only in the way it affects the expected income effects of trade for each individual.Education may be relevant here for other reasons-other causal mechanisms may be generating the observed association between education levels and protrade attitudes.We think there are two likely candidates:an ideational mech- anism that hinges on the role played by economic ideas and knowledge in the formation of economic policy preferences;and a cultural mechanism that relates commitments to key values,such as tolerance and cosmopolitanism,to attitudes toward foreign policy issues. The ideational argument is fairly straightforward.Highly educated respondents are likely to think about international trade in different ways compared to less- educated counterparts;the highly educated use a more sophisticated set of ideas about cause-and-effect relationships and more information about the effects of trade for themselves and for others.10 College-educated individuals,in particular,are likely to be far more informed than others about the aggregate efficiency gains associated with expanded trade,especially if they have had any contact at all with economics courses and with the theory of comparative advantage.While there is a firm consensus among economists on the virtues of trade openness,the counterin- tuitive loveliness of the law of comparative advantage makes it much more diffi- cult to convey the case for trade outside the college classroom.Studies of economic "literacy"among the public have shown that general measures of eco- nomic knowledge are strongly associated with education levels among individu- als,and college education in particular.2 Exposure to at least one college-level economics course is an especially powerful predictor of economic knowledge.Crit- 7.Stolper and Samuelson 1941.This theorem has been used extensively in the analysis of trade politics;see Rogowski 1989;and Hiscox 2002. 8.Scheve and Slaughter 2001b.9. 9.Mayda and Rodrik 2005,1409. 10.Among scholars who have examined surveys of public attitudes toward trade,the topic is typi- cally regarded as a complex issue about which most survey respondents have low levels of informa- tion;see Bauer,Pool,and Dexter 1972,81-84;Destler 1995,180;and Pryor 2002. 11.See Krugman 1993. 12.See,for example,Saunders 1980;and Gleason and van Scyoc 1995.472 International Organization incomes for those who own factors with which the economy is relatively well endowed (that is, labor skills in the developed economies), while disadvantaging owners of other factors (unskilled or low-skilled labor).' Scheve and Slaughter highlight as a "key finding" of their study the conclusion that "the preferences about trade and immigration policy align strongly with labor market skills."8 Mayda and Rodrik report that the results from their analysis of the importance of educational attainment in shaping views about trade are "strikingly supportive of the implications of the factor-endowments model and of the Stolper-Samuelson theorem." 9 Yet there are other, plausible, ways to interpret the positive relationship between the education levels of surveyed individuals and their support for trade openness. It seems particularly limiting to consider education only as a measure of workers' skill levels, relevant only in the way it affects the expected income effects of trade for each individual. Education may be relevant here for other reasons-other causal mechanisms may be generating the observed association between education levels and protrade attitudes. We think there are two likely candidates: an ideational mech￾anism that hinges on the role played by economic ideas and knowledge in the formation of economic policy preferences; and a cultural mechanism that relates commitments to key values, such as tolerance and cosmopolitanism, to attitudes toward foreign policy issues. The ideational argument is fairly straightforward. Highly educated respondents are likely to think about international trade in different ways compared to less￾educated counterparts; the highly educated use a more sophisticated set of ideas about cause-and-effect relationships and more information about the effects of trade for themselves and for others.10 College-educated individuals, in particular, are likely to be far more informed than others about the aggregate efficiency gains associated with expanded trade, especially if they have had any contact at all with economics courses and with the theory of comparative advantage. While there is a firm consensus among economists on the virtues of trade openness, the counterin￾tuitive loveliness of the law of comparative advantage makes it much more diffi￾cult to convey the case for trade outside the college classroom." Studies of economic "literacy" among the public have shown that general measures of eco￾nomic knowledge are strongly associated with education levels among individu￾als, and college education in particular.12 Exposure to at least one college-level economics course is an especially powerful predictor of economic knowledge. Crit- 7. Stolper and Samuelson 1941. This theorem has been used extensively in the analysis of trade politics; see Rogowski 1989; and Hiscox 2002. 8. Scheve and Slaughter 2001b, 9. 9. Mayda and Rodrik 2005, 1409. 10. Among scholars who have examined surveys of public attitudes toward trade, the topic is typi￾cally regarded as a complex issue about which most survey respondents have low levels of informa￾tion; see Bauer, Pool, and Dexter 1972, 81-84; Destler 1995, 180; and Pryor 2002. 11. See Krugman 1993. 12. See, for example, Saunders 1980; and Gleason and van Scyoc 1995