Language is often startlingly complicit in cultural attitudes, although sometimes it requires a good sobering-up to make this obvious… although perhaps that's just me. Anyway, I would like to begin by taking a close look at a brief sentence the Trek fans amongst you will instantly recognise: "He's dead, Jim." He's dead. He is dead. The first thing that we notice is that 'he' is still being referred to in the present tense, where it would be more accurate to reference the event of death and say: he died.
The word 'dead' is very common currency. In the word-finder freeware I habitually use (www.wordweb.info), twenty-one supposedly distinct definitions are offered for it as an adjective alone… and most of those pertain to inanimate objects which possess a physical existence before and after their 'death'. Now, a microwave doesn't forfeit any essential properties by ceasing operation; whereas personality doesn't just exist as a physical reality but as a concept with a temporal aspect.
As a collective noun, 'dead' seems fine, referring to 'people who are no longer living'… but as an adjective ('no longer having life') it can be misleading. As noted above, it's usually attached to a present subject; for example: "David is dead". If we translate this into literal meaning, we are saying: "David no longer has life", which is still to construe 'David' as being extant and able to be the present subject of the statement in some form or other. Now, we could propose that the concept and memory of 'his' personality endure in the minds of those discussing him, and we're not suggesting 'he' continues into some metaphysical realm... but the fact remains that most of us have, at some time, referred to deceased persons in the present tense more literally than this. It's hard not to, as English language is structured. Anyway, I just found this preconditioning rather fascinating, and thought I'd share... that's what this place is for, after all... :)