I am completely sure that an immortal man would be an insane man.You, a completely mortal creature, inhabiting a planet in which all creatures -- thinking and non-thinking -- are similarly mortal, declare that you are "completely sure" about the mental state of an immortal creature, one you've never met and can't really conceive of.
I'm completely sure that if biological immortality is ever achieved in humans (and that still won't preclude accidental death or murder, you know), that they will look back on your post here on this server (or the backup server it's been archived to) and smile.
(PS: For the purists reading this, I am aware that there are some single-celled organisms that are considered to be, in a certain sense, immortal.)
Amusing that you make the claim that I cannot possibly know what an immortal man might think... and then you go ahead and assume YOU know what an immortal man might think.
You have a serious problem with logic, doncha?
I'll just offer a thought experiment here, based upon well established theology, which has touched upon this same issue.
Biological immortality is achieved in humans and has been presented to us. It is documented in the person of Jesus Christ. Now before turning off the thinking light as soon as one reads His name as being a religious topic void of reason, I encourage the skeptical minded to continue to read.
The idea had been presented that if biological immortality is achieved, then accidental death and murder are not precluded. On the contrary, this manifests a framework in our thinking which presupposes many aspects of our anthropology which Scripture actually enumerates for us.
The topic of biological immortality is discussed in Scripture related to the resurrection of the body. The new body is composed of that which is immortal as opposed to what we presently have as mortal. Let's follow this a bit further.
One of many reasons our life here prior to the first death is so important, is that there will come a time when God's perfect Holiness will no longer tolerate the policy of evil in His midst, nor shall he surrender His fellowship with His family. There will come a point in time when certain basics are discerned in individual persons and a separation occurs. Also those with eternal life also have certain awards which have been created in eternity past, awarded to them as crowns which they will keep for eternity.
The assumption that accidental death and murder remain, fails to recognize that in eternity future, death is also removed from His presence. This is spoken about in Revelations 21:1-8.
When reading those Scriptures, consider why the separation of those who are murderers from God and those where death has past away, might be the very reason why murderers are removed from eternal life.
Good science fiction isn't based upon atheism or agnosticism, but is well honed from the many bible doctrines which have been manifest in Church History.
The topic of computerized neurology isn't new, but IMHO, even an adolescent approach should be able to discern between monasticism, dichotomous mind-body studies, and trichotomous Christan doctrines when discussing such issues. Identifying all human existence based upon the physical alone in one's sci-fi is like never advancing beyond the Wizard of Oz as a children's story. The challenging stuff if to discern body, soul, and spirit in our anthropologies and how we might best perform as God actually created us to perform by what He provides in those domains. Science is intuitively obvious childs' play compared to His Plan.