Greetings, Newguest, basically, alive does not allow for degrees of comparison. But, since the sense conveyed by text largely deals with philosophy and the amount of substance that makes living creatures more or less 'alive', it is possible here. More alive in this context most probably means that people, as opposed to animals, have certain additional qualities which other species lack, such as the capacity for intelligent thought, analysis and synthesis as well as acquiring and speaking languages that convey their thoughts, and not only primitive emotions.
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