Why mathematics isn't useful in general reasoning

John Doe is a typical Intelligent System.
As an Intelligent System he observes things and makes conclusions. Let's see how it looks like:

John wakes up at a morning, looks at his watch and sees that it's 8 am.
John remembers that 8 am is the beginning of his work day.
He knows that it takes 30 minutes to come to work.
John concludes that he'll be late at work.
John knows that his boss won't be happy about that.
John predicts what kind of consequences he'll get.
John tries to select actions which he should accomplish to mitigate the consequences of being late today.
John decides:
1) To skip his breakfast.
2) Call to his office from the car and apologize for the delay.

So, how could all this thinking process be described by mathematics???