[The physician and the computer. 30. Evaluation of time, different aspects of the same problem]

The authors mention different ways in which a give problem can be described within the framework of the theory of sets, logic, mathematical analysis, statistic and cybernetics. As an example of the confrontation of the mentioned aspects they discuss different approaches to the evaluation of time as a variable--temporal logic, Markov chains, theory of catastrophes which play a part in medicine, in particular in prognostic considerations. These different aspects make possible solutions which may differ and their application depends in particular on the purpose for which they are intended.