 Conversely, consider “mosquitoes carry West Nile virus”. This is a true relative generic on Cohen’s view. However, suppose that fleas also carried the virus, and did so at a somewhat higher rate than mosquitoes. Suppose further that the flea population swelled to immense proportions, so that fleas outnumbered all other insects. As the flea population increases, there will come a point at which mosquitoes cease to be more likely than the arbitrary insect to carry West Nile virus, and so the generic “mosquitoes carry West Nile virus” would be predicted to become false. It is perhaps natural to think, though, that these are circumstances under which “mosquitoes carry West Nile virus” would remain true—after all, one could still catch the virus from a mosquito! If this is correct, then it suggests that the analysis in terms of relative probability may not be correct (Leslie 2008).