The compatibility chart

A compatibility chart is not a single diagram but a procedure in three steps. The order matters, and the most common mistake is to begin with the second.

1. Each chart on its own

First each of the two birth charts is read separately: temperament, the capacity for relationship, the condition of the seventh house and of its ruler, Venus and Mars, the Moon.

Anyone who compares two charts without knowing them individually is comparing something they do not know. And much of what looks like a problem of the bond is a disposition in one of the two.

2. The comparison — synastry

The positions of the one are laid over the chart of the other. What counts:

the aspects of the lights crosswise — Sun and Moon, in both directions;
Venus and Mars crosswise;
the rulers of the first and seventh houses in both charts;
and above all reception: is a planet of one of them in a sign ruled by a planet of the other? In the tradition it counts for more than the aspect itself, and modern accounts almost always leave it out.

3. Time

Two people meet at a given moment, and both are then in a particular stretch of their lives. The same bond can hold in one year and not in another. Without the timing techniques the comparison remains a snapshot without a date.

And the composite?

The composite chart — calculated from the midpoints of both charts — is a twentieth-century method and does not belong to the classical technique.

Anyone who works with it should know that it describes no real state of the sky: it is a computed quantity with no moment and no place. That does not make it worthless, but it rests on different ground from the rest.

The requirement that comes before everything else

Both must know that the reading is being done.

Reading the chart of someone who has not asked for it, in order to find out something about them that they do not tell of their own accord, is not done here — however understandable the wish.

What comes out of it

A description of where two people will rub against each other and of where they will come easily to one another. Not whether a relationship lasts: a comparison with many tensions describes a demanding bond, not a doomed one — many long marriages look exactly like that.