I didn't know Ralph Miliband well. To the best of my recollection, I met him in person only twice: once at a conference in Brussels in the 1980s, the second time at a gathering in London to mark the publication of one of the editions of The Socialist Register. The two connections in which I knew him better were as editor of that annual and as the author of the books and essays for which he came to be widely known as a Marxist academic. Ralph solicited some of the essays I wrote for The Socialist Register, one of which in particular was to have a marked influence on how I subsequently came to think about the relationship between Marxism and morality and questions of political ethics more generally, and so I owe him a large debt in that regard. As an editor he was, in my experience, always creative, helpful and straightforward.
However, it was for his work above all that I, like many others, valued Ralph's contribution to the thinking of the left. I didn't agree with him in everything, and indeed in a later piece for the Register, written as a tribute to him, I took issue with some of his ideas about the sources of great cruelty in human affairs. Still, Ralph was one of those writers on the left whose works I always looked forward to reading. He wrote in a clear and compact prose, uncluttered by needless jargon and informed by an evident moral seriousness that wasn't in hock to any narrow orthodoxy. His reputation as a Marxist thinker was earned by the consistent quality of his intellectual output.
From mutual friends who knew the family better than I did I had gathered that Ralph's sons had reasons enough for being proud of their father. But beyond those familial reasons, Ralph's stature in the public domain was also something of which they could be justly proud. No smear campaign against him will be able to erode that.
(See also this old post.)