At first I thought the Cardinal was just saying anyone who fails to consider the transcendent has an impoverished conception of what it is to be human. But at the end he is clear that those who fail to consider such bigger questions are themselves not fully human.
Well, in a way, I would agree. The Cardinal's mistake, I think, is not in suggesting that someone who never thinks about the bigger questions is lacking in an important dimension of human existence - that may be true (it's a weaker claim than the Socratic assertion that the unexamined life is not even worth living) - but in supposing that atheists never think about such questions, and indeed have no time for them. This is the popular straw man fallacy endlessly wheeled out against atheists: they don't even ask such big questions, but just dismiss them as worthless. I have previously commented on it here (where I point out Rowan Williams also commits the fallacy).
I could spend more time unpacking the various muddles the Cardinal gets into here (such as e.g. he seems to conflate (i) saying that a conception X of humanity is importantly deficient re humanity, with (ii) saying that those who have conception X of humanity are importantly deficient re humanity), but it is also worth just drawing attention to the fact that going round saying that those with whom one most profoundly disagrees are "not fully human" is an extraordinarily insulting and dangerous thing to say, whether true or not.
Religious folk regularly moan about Dawkins being rude and insulting to religious people. This, surely, is far, far more insulting. I get the impression it's intended to be.
Isn't the Cardinal at least aware of the disturbing connotations of the phrase, "They are not fully human"? It is surely most closely associated with mass-murdering dictators and eugenicists. If I really am not fully human, according to the Cardinal, I wonder to what lengths he might be prepared to go to make me fully human? And does he consider my not-fully-human existence worth less than that of a fully-human religious person? The use of this chilling phrase is, at the very least, bad PR for the Catholic Church.