Another quote from 20th century British astrologer Ingrid Lind's out-of-print little book Astrology and Commonsense (1962). Here she considered astrological Sun.
SUN: Stands for the male principle. It "rules" or has affinity with the sign Leo.It's useful to be reminded that a "strong" position of the Sun in a natal chart can seem to endow the individual with Leo-type characteristics. There's a snag though: an exact time of birth is required before the Sun's position (chart-wise, not sign-wise), can be established.
Keywords: power, vitality, self-expression.
The sign of the zodiac containing the Sun at birth can be known by the birth-date alone, without reference to exact time. For many this constitutes the whole art of astrology and they will tell you that they are Leo, Taurus, Libra, as if by virtue of having Sun in a given sign they were the sign's embodiment. But while the Sun's position strongly affects the individual this is a gross over-simplification. In any chart the Sun should be studied quite separately from its sign-position before any conclusions are formed. Its strength is highly significant: for instance if rising exactly or overhead it fortifies the personality and enhances the likelihood of (or urge for) prominence. If it strongly aspects other planets the strength of such planets is increased, for the Sun empowers all it touches.
Solar traits are similar to those of the sign Leo, which is "ruled" by the Sun; and a strongly aspected Sun can correspond with characteristics associated with those of Leo regardless of the sign it is in. Too much Sun tends to make the individual overbearing ("too much" could be the Sun rising, where it strengthens the ego, and in strong but not easy aspect to other planets, or it could result from too many planets in Leo.)
When considering the Sun, as indeed any single factor, the general picture of the chart with its strengths and weaknesses must be kept in mind. A chart (or person) can be strong enough to support an overbearing Sun; but, if otherwise weak or afflicted, as will be shown in the chart, the pronounced characteristic is nothing but a nuisance to its owner, since it will only accentuate the difficulties of his make-up.