Life used to have four molecules known as G, T, C and A.
Readers, now meet X and Y.
Scientists have successfully created DNA which can carry the extra molecules and replicate itself. In other words the language of life has just gotten more complicated unnecessarily.
Does life really need the extra pair of molecules? We have done well, without exaggeration, for billions of years with only four molecules. So why add extra. It’s rather like saying let’s add a new letter to the English alphabet. Why try to do so when twenty-six letters have been sufficient for this long.
Nonetheless this shows us that life and language have no limits, and that both make do with the material at hand to perform what is necessary.