In fact, this multiplicity and divergence are the cause of most disorders and even illnesses. Something is going well, you have caught the guiding thread, you are following your path, you think you are going to get a result, and then, suddenly, there! — something happens quite unexpectedly, you did not know it was there: it wakes up and insists on joining the march. But it creates a terrible disorder and you must begin everything over again.
Ref: Questions and Answers 1957–1958