Doctrine of Signatures

Nature Wisdom - Signs - Symbolism

Where nature's secrets come to life.
" your exuberance when telling us about the herbs." 
" to spend an early evening like this." 
"This course brought so much into awareness for me."
“Images, similars, signs, correspondences, and coincidences infer a different way to look at the world; they give rise to a different kind of knowledge.” - Matthew Wood

Discover what's hidden in plain sight!

The Doctrine of Signatures is used around the world in pre-modern cultures where thought-by-association is accepted as a valid means of obtaining knowledge.

These classes are part of the unique and central concept of the Matthew Wood Institute of Herbalism curriculum: Nature Wisdom.
The idea is that a plant looks like the disease, organ, or person it can heal.

For instance, Celandine (Chelidonium majus) has yellow/orange sap like bile. It was official in the U. S. Pharmacopeia until 1951 for “biliousness;” now they just remove the gallbladder.
Horsetail (Equisetum arvensis) looks and feels like course horse hair, so it is good for the hair. Actually, it is beneficial for nearly all connective tissue. It also grows on wet sands, so it is a remedy for the kidneys.

Thus, the shape, color, sensory impression, and habitat all can be used to determine the uses of a plant.
The putrid smell and bad taste of Figwort (Scrophularia spp.) indicate that it is a remedy for putrefaction. Since it has gland-like or hemorrhoids-like flowers, it is called Figwort and Pilewort and used as a lymphatic and hemorrhoid remedy.

Who is this for?

Do you love plants, herbalism, metaphor, and being in wonder and awe of this vast world? This is for you! This is for all experience levels, beginner to advanced.

Enjoy on-going exploratory and interactive classes. Each month Leigh will guide us in discovering the signatures of a new herb or concept; encouraging and helping students to see this amazing plant world through new eyes, or perhaps simply with a new perspective. Check the calendar for the next live class date. Matthew will chime in on occasion too!
Herbs and Concepts Covered:
  • Burdock - Arctium lappa
  • Cedar - Thuja occidentalis
  • Cleavers - Galium aparine
  • Coltsfoot - Tussilago farfara
  • Creeping Charlie - Glechoma hederacea
  • Goldenrod - Solidago spp.
  • Hawthorn - Crataegus
  • Motherwort - Leonurus cardiaca
  • Nettles - Urtica dioica
  • Oak - Quercus spp.
  • Pasque Flower - Pulsatilla spp.
  • Plantain - Plantago spp.
  • Prickly Lettuce - Lactuca spp.
  • Rabbit Tobacco - Pseudognaphalium obtusifolium
  • Solomon’s Seal (Polygonatum spp.) and False Solomon’s Seal (Maianthemum racemosum)
  • Sumac - Rhus spp.
  • Sunflower Seed - Helianthus annuus
  • Thyme - Thymus spp.
  • Trillium
  • Vervain - Verbena spp.
  • Violet - Viola spp.
  • Walnut - American (Juglans nigra) and European (J. regia)
  • White Pine - Pinus strobus
  • Wild Bergamont - Monarda fistulosa
  • Wild Geranium - Geranium maculatum
  • Shape
  • Colors
  • and more!
Join today

You'll learn:

  • What are the signatures
  • What the signatures mean
  • History, myth, and lore
  • Herbs, Astrology and more!

Free Option

Engage in discussions and share your insights with others by joining the Doctrine of Signatures Facebook Group

This is where the magic happens BEFORE the live class.

Get started with a Free Intro Class & Cards!

Paid Option

  • Get access to the free option and all previous classes. 
  • Download the amazing slide shows!
  • At least 6 new classes per year.
  • Online support from teachers.
  • Certificate Included!
  • Join new, live classes with the Professional Library and Pay Once (3-month access) payment options.

Free Doctrine of Signatures Starter Set

Access this FREE intro to the Doctrine of Signatures with Matthew Wood, MS, and Leigh Arnoldy, BM, and discover our 13-card guide on plant appearance and properties.


Leigh Arnoldy, BM

Leigh has nurtured a deep connection with nature since her early years, immersing herself in outdoor adventures like camping, hiking, and nature identification. During her journey, Leigh fell into a pile of astrology books and hasn’t crawled out since. Leigh returned to her nature-loving roots and brought with her love of mythology and the esoteric. In 2016, she became a student of the MWIH. She offers local herbalism classes. On her website, she delves into the signatures and connections in the natural world.

Certificate Included

  • How to Get a Certificate

    • Complete course materials
    • Pass the test with a grade of 70% or better
    • Save or print your certificate!

    Available with subscription and individual course purchases.

  • Accreditation hours

    This course is a total of 2 accredited hours
    • 2 hours History, Philosophy, and Therapeutic Paradigms and Applications (Including Energetics) of Various Systems of Herbal Medicine

    *Please check with your accrediting agency whether they will accept accredited hours or certificates from the Matthew Wood Institute of Herbalism
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Doctrine of Signatures

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