I would like to direct your attention to Wm. Lilly. He does something which I would probably not consider. He provides a table to evaluate the strength of the Part of Fortune. (CA p. 145)
I’m not going to repeat the table here. Instead I would like to examine what he does in assigning the “dignities and debilities”. I think the main factors are whether Fortuna is under the influence of the benefics or the malefics or whether placed where either the Sun and Moon have strong essential dignity. So Fortuna is strengthened tremendously when in Taurus or Pisces but is debilitated when in Scorpio, Capricorn or Aquarius. Aries is neutral because although ruled by Mars the Sun is exalted there. What is notable is how Fortuna in Gemini and Virgo are weighted. Jupiter is in detriment in Gemini but the North Node (which is considered as being of the nature of the benefics) is exalted there. So weak dignity for Fortuna. In Virgo where Venus is in fall and Jupiter is in detriment, Fortuna has weak dignity only when in the terms of Venus or Jupiter. From our previous discussion on the Part of Spirit it seems a matter of common sense that reversing the dignities is not true. The Part of Spirit is not strengthened by being where the malefics are strong. So Lilly’s table for Fortuna applies equally to the Part of Spirit.
There are many excellent articles on the internet, that discuss the Part of Fortune.
It is my intention to stimulate thinking about these Parts. I leave it to your discretion dear reader whether you want to use the Part of Spirit or not and whether you want to reverse the formula. There have been many excellent articles on this theme, also on the internet and so I will list a few here.
There was a comment made by Andrew Carter, the date is somewhere in August 2005, to an article on Fortuna which I would like to quote as it is buried deep in the internet and not easily found. I think it brings another aspect to the discussion and is worth being “unearthed”:
… Bonatti writes: “The significations of the pars fortunae appear more during the day . . . the pars futurorum appear more at night.” This means that if I reverse the formula for birth (since I was born in the night), the pars fortunae in my chart is in Pisces (my day-formula pars futurorum) and the pars futurorum in my chart is in Leo (my day-formula pars fortunae). But this is a distinction without a difference, because Bonatti also states that “the significations of the pars futurorum appear more at night.” This means that I would place more emphasis on the “significations” of the part of spirit in my night chart which, in my case, is in Leo: the part of fortune using the day formula. Bonatti advised: reverse the formula, yes, but also reverse the significations. In other words, it makes no difference whether you reverse the formula or not, because in either case, the emphasis will remain on where the Moon would be in a day chart. The Moon does not turn into the Sun simply because one is born at night: the Moon remains the Moon and the part associated with it (pars lunae) acts as a container for lunar influences.
Some astrologers understand this as “use the day formula – but, the part of fortune will be emphasised in a day birth, whereas the part of spirit will be emphasised in a night birth.” If you want to read the entire comment click here.