On the current court, for example, Justice Anthony Kennedy and retiring Justice Sandra Day O'Connor are often described as having moved to the moderate center, or perhaps even further to the left, while Justices John Paul Stevens and [David Souter]--Republican appointees, like O'Connor and Kennedy--are said to have become aggressive liberals. But judged by the standards of the last half-century, all four justices are just what one would have expected when they were appointed: Kennedy and O'Connor are solidly conservative, and Stevens and Souter are moderate conservatives.