"In the present case the applicant says, and says forcefully, that he does not accept the reasons that were given. We are not to be taken as finding that the respondent's complaints against the applicant are in fact justified. The applicant himself advances no alternative reasons for his dismissal. We cannot find that the reasons given by the respondent in the letter to which I have referred were untrue or were inadequate in the sense that the respondent actually relied upon some other reasons."