Re: Extraterrestrial life

From
Date
     Chip -- hope you don't mind my forwarding this to the net, as the 
     point you make is a good one and deserves airing more generally.

Subject: Re: Extraterrestrial life
Author:  cpretzma@magnus.acs.ohio-state.edu (Chip Pretzman) at Internet
Date:    20/08/96 20:54
     
 The martian problem is something else again, as there are no 
>     life-forms on Mars that we know about with which we can make a valid 
>     comparison -- and we cannot formally make such valid comparisons with 
>     terrestrial life forms, by definition.'
     
So how, Henry, do you get the first life form to begin a comparison?  This 
is a paradox.  

Chip, you're right, it is: but there is a solution. I expect that 
extraterrestrial life-forms will have to be identified by a set of criteria 
independent of morphology or chemistry, such as reproduction, local entropy 
decrease and so on. Of course, these cannot be applied to 'fossils' for 
which chemistry and morphology are all we have. 

You write:
In my opinion, it is very dangerous to attempt to discover life on Mars and 
bring it back here alive.  We should not send people to Mars, nor return any 
material. 

I suspect that NASA folks take matters such as microbial containment very 
seriously, even those folks who've never seen the X-files. A distinguished 
authority on fossil microbes told me recently how he'd been asked to 
participate in containment protocols for such eventualities. 

You write further:
      I am assuming that all of the planets in our solar system formed from 
     the same stuff, therefor, everything being equal, life on another 
     planet should be equivalent to ours.  With the possibility of 
     biological crises in hand, leave it on Mars.

Possibly, but it is *still* an assumption
>     
     
     Henry