How much does Poul Anderson tell us about the Holont in Starfarers? Not enough, really. They are quasi-stable quantum states in the virtual particles of the vacuum in the changeable space-time near a black hole, bearing information, therefore alive, and communicating linguistically, therefore intelligent. But we do not read any conversations with them as we do with the organic intelligences encountered by the starfarers. Instead, a human character summarizes communications for her colleagues and thus for the reader. Before that, the narrator had summarized holontic evolution.
Forms of quantum states appeared, linked, multiplied and became an intricate set of codes, mutated by the uncertainty principle, until some were a thinking mind differentiating itself into individually living waves or avatars that re-coalesce and redivide at will, experiencing lives and histories that resemble memes in organic minds, but also, like organic minds, acting to change their states and those around them, their actions detectable as photonic, electronic and nuclear events, then as dialogue with organic beings when the latter approach the black hole in spacecraft.
Anderson's account is extremely condensed. I found it difficult to paraphrase but otherwise would have understood little and would have retained even less of what he had written. I hope that my account is interesting and informative for other readers.
Thought requires symbols which require language which is social so I suggest that holontic differentiation preceded thought.
The Holont have two obvious unrealised potentialities. I am sure that there are more but I do not know enough science to draw them out.
A sympathetic human character, Jean Kilbirnie, dies in the black hole. Or does she? In fiction, and particularly in fantastic fiction, when no body has been found, the author might reverse the death. Two of Jean's colleagues later suspect that holontic configurations are not transitory but permanent, imposing a trace on the vacuum, a direction on randomness, a change in the metric, thus lasting and surviving death, implying that organic patterns and processes might last also.
So could the Holont rescue Jean's consciousness from the death of her body? This is my speculation, no one else's, but it is implied by passages that otherwise are left undeveloped. Anderson's intention is to show us that there is always more to be learned so there will at any stage be still unanswered questions.
Starfarers, a long novel that had already incorporated the Kith series, could, like other Anderson works, have had a sequel. Jean had not returned by the end of this novel but -
To be continued.