10. In the ordinary action in negligence where the plaintiff is a passenger who has been injured in a motor vehicle driven by the defendant, the relevant relationship of proximity is simply that of driver and passenger and the category of case is the general one which reflects that relationship. In that general category of case, the standard of care required, being objective and impersonal, is not modified or extended by the personal driving history, ability or idiosyncrasy of the particular driver. It is the degree of care and skill which could reasonably be expected of an experienced and competent driver. That is not, however, to say that, regardless of the circumstances of the particular case, the relationship between a driver and a passenger is, for the purposes of the law of negligence, a completely standardized one or that the content of the duty of care where that general relationship exists is necessarily immutable. While the personal skill or characteristics of the individual driver are not directly relevant to a determination of the content or standard of the duty of care owed to a passenger, special and exceptional facts may so transform the relationship between driver and passenger that it would be unreal to regard the relevant relationship as being simply the ordinary one of driver and passenger and unreasonable to measure the standard of skill and care required of the driver by reference to the skill and care that are reasonably to be expected of an experienced and competent driver of that kind of vehicle. It would, to take an extreme example, affront the standards of the reasonable man of the law of negligence to define the duty of care which a mentally retarded and completely unqualified and inexperienced person owed to a professional pilot who had persuaded him or her to attempt to pilot an aircraft in which they were both travelling as being the skill and care that are reasonably to be expected of a qualified and experienced pilot. The point can also be illustrated by reference to a more mundane example which is closer to the circumstances of the present case, namely, that of a professional driving instructor and a pupil having his or her first driving lesson. It would be contrary to common sense and the concept of what is reasonable in the circumstances (considerations which are basic to the common law of negligence) to measure the content of the duty of each of such an instructor and such a pupil by the standard to be expected of the ordinary experienced, skilled and careful driver, with the result that the degree of skill required of each of them toward the other was the same. Where such special and exceptional facts transform the relevant relationship, questions of the requisite proximity of relationship and of the standard of any duty of care must be determined by reference to the more precisely confined category into which the particular relationship falls. Assuming that the requirement of proximity remains satisfied, the standard of care, while remaining an objective one, must be adjusted to the exigencies of the relevant relationship in that it will be the degree of care and skill reasonably to be expected of the hypothetical reasonable person of the law of negligence projected into that more precisely confined category of case. The point may be illustrated by reference to the abovementioned example of a professional driving instructor and a pupil having his first lesson. In relation to other users of the highway, the duty of care of both instructor and pupil will ordinarily fall to be measured by the same objective standard since the relevant relationship will be the ordinary one between a driver and another user of the highway. As between themselves, however, it would be to state a half-truth to say that the relationship was, if the pupil was driving, that of driver and passenger. The special circumstances of such a case remove the relationship into a distinct category or class which, while possessing the requisite degree of proximity, could not rationally be seen as giving rise to a duty to drive with the skill reasonably to be expected of a competent and experienced driver. Indeed, it is the very absence of that skill which lies at the heart of the special relationship between the driving instructor and his pupil. In such a case, the standard of care which arises from the relationship of pupil and instructor is that which is reasonably to be expected of an unqualified and inexperienced driver in the circumstances in which the pupil is placed. The standard of care remains an objective one. It is, however, adjusted to fit the special relationship under which it arises.