With regards to sacred geometry, there has been a beautiful book out for just over 20 years by Robert Lawlor titled
Sacred Geometry, isbn 0-500-81030-3, which I would highly recommend... it is a lovely and illustrated book... and a number of illustrations from earlier times recall
I the Bateleur/Magician (p 7) and
XXI the World (p 11).
I personally agree with what has been said before, that one does not need to already have studied vast areas in order to read with the Marseille - if such was the case, then I suspect no-one would ever be able to divine using the deck.
What
is important, in my personal view, are the twin sides of deepening understanding by, on the one hand, that study for which none of us ever has sufficient time, and on the other, and very importantly,
reflection upon what one sees and compares and links and intuits - even if these seem at first a little silly.
For example, just looking at the averall image of the Three Coins - and let's forget they are coins at first - what is the general image formed? To what does it remind one of? In reflection, does it begin to move in ways have take on its own life? - now doing the same with the same card but beginning with it in the reversed position to what has just been done, what there emerges?
That they are Coins - what does this mean? What
are coins? what is the significance of the 'preciousness' of the metal? Why use metals which, generally, do not tarnish - and why use metals which do? - That even
metal, not wood or glass or paper is used, what of that? And what impact has this had on ways of determining the value of certain items - or even one's worth!?!?
What of 'three' - how does this differ from two, or from four? In how many ways could three items be arranged? How does each arrangement differ in the image it makes and how it makes one respond?
Could the 'floral' aspects to the cards have been done in quite different ways? Is there much, little, or just an amount which suggests... what? And what of the flowers there? Are they budding or full? What does this suggest? The leaves, are they growing or decaying? What does this seem to suggest? And what is growth and decay in any case?
The colours used - what do they seem to suggest???
I'll leave it here for now... the point being that much reflection and 'study' may be undertaken - certainly much with books, but restricting oneself to books is also not looking at the cards themselves and reflecting on the
images they present.
This '
study' is as important as the one done from the reflections of others and written in books... or in threads.
For the major Arcana, much may be written of the images and their connection to yet other earlier or later similarity and the ways they may have been variously sourced and understood...
...
some aspects of numerological considerations can likewise take place with regards to numerals. Foremost, however, is to reflect, for then what one reads may also be perhaps better understood and appropriately questioned.