Tax, one of the issues with modelling a non linear system is that non linear systems require infinite precision of the initial conditions to exactly reproduce results. This is an impossibility. It puts a limitation on what the models can do and is a valid mathematical statement.

Therefore if the person I was responding to demands perfect reproducability in a model before he believes it has any validity, he is demanding a mathematical impossibility, which is an unfair restriction.

Would you care to tell me why mathematics is getting dinged?