Midpoint tree

Meaning

A midpoint tree takes one factor in the chart, a planet, the Node or an angle, and lists beneath it every pair of other factors whose midpoint falls on it within the orb, usually on the 90° dial. The factor at the top is the trunk; each pair is a branch. The branches are listed from the closest to the widest.

Written out, a tree looks like a chain of planetary pictures that share the same third factor:

Saturn = Uranus/Neptune = Sun/Venus

Each branch is one picture (Saturn = Uranus/Neptune, Saturn = Sun/Venus). The tree adds nothing new to the arithmetic. What it changes is the reading: instead of meeting the pictures one by one in a long list, the astrologer sees everything that comes to a focus in Saturn at once.

A factor with no branches has no tree. A factor with many branches is a busy point in the chart, where many pairs of influences meet.

Origin and history

The tree arranges the planetary pictures of the Hamburg School and of cosmobiology, and the per-factor layout goes back at least to Reinhold Ebertin. In Applied Cosmobiology he advises working out the "cosmic condition" of each factor before reading the chart: its place in the zodiac, its aspects, and the midpoints it stands on, written in one line such as Sun = Moon/Mercury = Moon/Pluto (pp. 22–23) [5]. Listing this for every factor gives what he calls the structural elements of the chart; his example is Goethe's chart, and he designed a chart form (KS 2) with room for the list and for notes from his Combination of Stellar Influences beside it (pp. 26–27) [5]. Elsewhere the book calls the form one for "cosmic structural pictures", and defines a structure picture as the composite of these elements (pp. 114, 200) [5]. Ebertin's layout also lists aspects, so it is a little wider than a midpoint tree, but the midpoint part is the same thing. The Combination of Stellar Influences gives a short interpretation for each pair and for a third factor on its midpoint, so a tree can be read by looking up its branches one after another [1]. Munkasey's Midpoints can be used in the same way [3], and Harding and Harvey's Working with Astrology is a fuller modern guide to reading midpoints [2].

"Midpoint tree" is a name used in astrology software; the Kepler program, for example, offers midpoint tree diagrams alongside midpoint listings [4]. Where the name first appeared is uncertain.

How it is used

• Where to start. Most readers begin with the trees of the personal points: the Midheaven, Ascendant, Sun and Moon. They then look at the trees of the other planets. Ebertin's worked example begins with the Sun and Midheaven (pp. 22–29) [5].
• Writing the pairs. Ebertin writes the faster-moving body of each pair first, as in his Combination of Stellar Influences, with the Sun before the Moon and the Midheaven and Ascendant last, so that each branch can be looked up directly (p. 23) [5].
• Tightest first. The closest branches are read first and given the most weight; branches at the edge of the orb are read last, or dropped when a tighter orb is used. Ebertin allows 1½° and puts a branch he admits with a wider orb in brackets (pp. 23, 27) [5].
• Repeated themes. If several branches of one tree share a planet (for example two branches both involving Neptune), that planet's theme is emphasised at the focus.
• Overlapping trees. When two factors are conjunct or in hard aspect, they sit close on the dial and their trees share branches. The two trees are then read together.
• Contacts. Each branch is either on the midpoint (conjunction) or reaches it by opposition or square (on the 45° dial also semi-square or sesquiquadrate). Practice differs on whether the conjunction should count for more than the other contacts; Ebertin treats every multiple of 45° as of about equal value (p. 3) [5].
• Timing. A transit or direction to the focal factor touches every branch of its tree at once, which is why the tree of a busy point is watched closely in forecasting.

The same information can be seen from the other side in the midpoint sort, which lists every midpoint in dial order, and in the midpoint cluster, where several midpoints fall together whether or not a planet is there.

On this site. The Trees view builds one tree for each point that has at least one picture within the chosen orb (0.5° to 3°, default 1.5°) on the chosen dial. The busiest points come first (most branches), and within each tree the branches are listed tightest first, with the orb and whether the point is on, opposite or square to the midpoint (or on the 45° and 22.5° dials, the smaller hard steps). A factor never appears as a branch of its own tree. The Ascendant and Midheaven have trees, and appear in branches, only when the birth time is known.

Examples

Albert Einstein (14 March 1879, 11:30 local mean time, Ulm), 90° dial, orb 1.5°, the ten planets only. Seven planets have two branches each:

Mars, Jupiter and Venus have one branch each: Mars = Venus/Neptune 0°31′, Jupiter = Moon/Neptune 1°17′, Venus = Sun/Neptune 1°18′.

Two things show up. Mercury (3°09′ Aries) and Saturn (4°11′ Aries) are conjunct, so they share the Uranus/Neptune branch, and their trees are read together. And Neptune turns up as one half of a pair in six of the trees, a repetition a reader would note before interpreting any single branch.

See also

Planetary picture for a single branch, and midpoint cluster for groups of midpoints with or without a planet.