by Robert ten Hoor 13. February 2018 13:26

This is a very short post with a thought of today... I just saw a clip on youtube about what life is.

When is something alive, when is it not?
Thinking about this, I came up with the following definition:

Something is alive when it uses energy to decrease entropy.

In a closed system, you would expect entropy (a vague term, I admit) to increase. A gas will spread over a larger space, a stone will evaporate etc.
Living organisms, however, tend to grow: they will get more organised.

In other words, if something is not alive, it will dissolve in it’s environment. It’s entropy will increase, it will become more ‘chaotic’.
So, according to this definition, here are some examples of living organisms:

  • Animals
  • Plants
  • Bacteria, some cells
  • Viruses

Not living then:

  • DNA strands by themselves
  • Computers
  • Computer programs (Artificial Intelligence, Computer Virusses) Even if they are Artificial Intelligence: leave a computer for a number of years and it will decay. The ‘direction’ is for increasing entropy.
  • Parts of cells




Add comment

  • Comment
  • Preview

Real Time Web Analytics