So value is only found in the lives of things capable of discerning beauty and good ? So would killing severely mentally handicapped people not rob them of any value or seriously harm them ? And is there even such a thing as good or beauty or are these not manmade concepts with only selfimposed value ? I just think that value and how we assign it is a very personal , subjective and convenient thing . I think the only way to attempt to be objective about it is to look at how each creature exists independently in its environment and what purpose they serve within that ecosystem . Imagine saying salmon have no value because they can ' t determine beauty or good and then , on that basis , killing all the salmon for food until you ' ve depleted their population . Then maybe you ' d see they were actually valuable after all .