H. P. Blavatsky

Substance. Theosophists use the word in a dual sense, qualifying substance as perceptible and imperceptible; and making a distinction between material, psychic and spiritual substances (see “Sudda Satwa”), into ideal (i.e., existing on higher planes) and real substance.

Source: H. P. Blavatsky, The Theosophical Glossary, art. Substance