I wonder how much irony Macaulay intended when he came out with this epigram. As every schoolboy knows, he would occasionally tie himself in knots when displaying his cleverness.
To me, he’s getting at the danger of relying on a generalization so much that it becomes stereotype. I had a good definition of the difference on my laptop, but I can’t find the file with the exact quote. However, I found the distinction drawn here to be useful:
A stereotype is an ending point. No attempt is made to learn whether the individual in question fits the statement…. A generalization, on the other hand, is a beginning point. It indicates common trends, but further information is needed to ascertain whether the statement is appropriate to a particular individual.
We can’t live without generalizing, or at least I can’t. I need to make educated guesses about how to navigate the world and its individuals all the time. In some ways, I believe prejudice is a crime of laziness. It happens when I can’t be bothered to look past the archetype to the individual beyond.