The ‘primacy principle’ comprises three assumptions about political orientations. The first is that they are learned during childhood. The second is that this childhood learning further shapes any subsequent modifications of them. The third is that the scale of any such subsequent modifications is small: fundamental political orientations tend to endure through life. We propose, using cohort analysis, to examine the extent to which three political orientations – party identification, political efficacy and political trust – do, as a matter of fact, endure through adulthood.