In Glasgow Corporation v Muir [1943] AC 448, Lord Macmillan stated:

The standard of foresight of the reasonable man is, in one sense, an impersonal test. It eliminates the personal equation and is independent of the idiosyncrasies of the particular person whose conduct is in question. Some persons are by nature unduly timorous and imagine every path beset with lions. Others, of more robust temperament, fail to foresee or nonchalantly disregard even the most obvious dangers. The reasonable man is presumed to be free both from over- apprehension and from over-confidence, but there is a sense in which the standard of care of the reasonable man involves in its application a subjective element. It is still left to the Judge to decide what in the circumstances of the particular case the reasonable man would have had in contemplation and what, accordingly, the party sought to be made liable ought to have foreseen.

One consequence of the approach in Glasgow Corporation is that it leads to the courts imposing a higher or different standard of care on the defendant where it considers that this is appropriate.