Most people divide mankind emotionally into friends and enemies, feeling sympathy for the former, but not for the latter.
 Bertrand Russell, A History of Western Philosophy (1945). copy citation

Context

“But the development of this feeling is very different in different people. Some find pleasure in the infliction of torture; others, like Buddha, feel that they cannot be completely happy so long as any living thing is suffering. Most people divide mankind emotionally into friends and enemies, feeling sympathy for the former, but not for the latter. An ethic such as that of Christianity or Buddhism has its emotional basis in universal sympathy; Nietzsche’s, in a complete absence of sympathy. (He frequently preaches against sympathy, and in this respect one feels that he has no difficulty in obeying his own precepts.)” source