Perhaps it was the format ... this is a collection of six essays (plus some additional material) presented as lectures at the University of Milan over two days back in 2003, each running somewhere around 20 pages. I assume that, being a college professor, Davies would not be daunted at presenting six lectures over two days (as opposed to most business speakers), but the format does not lend itself to particular depth on any topic. Also, as per the sub-title, everything he's approaching here has an over-laid "philosophical" spin, so not only does he have to present a "getting up to speed" scan of a topic, put it out within the context of "Are We Alone?", but then step into philosophizing over the various implications.
The topics here are: "A Brief History of SETI", "Extraterrestrial Microbes", "Alien Message", "The Nature of Consciousness", and "Alien Contact and Religious Experience", along with appendixes on "Project Phoenix" and "The Argument for Duplicate Beings" (which obsessive readers of this space may recall was a notable point in a book reviewed a few months back).
Frankly, I was made somewhat uncomfortable several times in this book where Davies seems to be making a point to push into "philosophies" amenable to his Papist hosts by taking somewhat uncalled-for shots at the likes of Richard Dawkins and Stephen Jay Gould (ala "The Neo-Darwinian Contingency Argument"). Fortunately, it eventually becomes clear that he is not so much arguing against antitheistic stances as he is arguing for the "crystal-like" tendency towards complexity, and, ultimately, consciousness.
Of course, one of the core arguments for the "we're alone" forces is that if there were other beings out there, and there were some that were more advanced than us, then how come we haven't (despite on-going efforts) found any? One model he charts out is that of "planet hopping" colonization, where creatures (or their more-or-less sentient machines) would spread out across all the occupiable planets in the Galaxy within a span as short (!) as a million years. In a Galaxy that's 15 billion years old, that's a blink of an eye, and should have happened repeatedly.
Anyway, while there are interesting bits like this in here, the book as a whole is a something of a meander ... trying to stay within a thematic concept, and an over-lying "spin", it skips in and out of various concepts, without really providing a substantial look at any. Not surprisingly, this hasn't managed to stay in print (unlike many of Davies' other titles), but is available in the used market. The Amazon guys have "acceptable" copies for as little as a penny, with "like new" copies starting around two bucks. This isn't a bad book, just nowhere near the author's better efforts.