Piet Mondrian (1872 to 1944) was a Dutch artist who developed a non-representational style called Neoplasticism. Although he passed through a vaguely Cubist phase, he was not a true cubist. He was a Theosophist, studying the work of Madame Blavatsky, and he developed his abstract art as he developed his spiritual philosophy. He believed that it was possible to render the true nature behind the actual form of a thing. Only the simplest possible elements were allowed, in order to get as close as possible to the ideal. Horizontal and vertical lines in black, filled with blocks of primary color or white, laid out with intuitive artistry, were the closest one can come to representing this underlying truth.
According to the Tate Gallery's online article on Neoplasticism, his essay 'Neo-Plasticism in Pictorial Art' sums up his artistic philosophy: 'As a pure representation of the human mind, art will express itself in an aesthetically purified, that is to say, abstract form …The new plastic idea cannot therefore, take the form of a natural or concrete representation … this new plastic idea will ignore the particulars of appearance, that is to say, natural form and colour. On the contrary it should find its expression in the abstraction of form and colour, that is to say, in the straight line and the clearly defined primary colour'.
According to Hermetic.com, in this review of the Book of Dyzan Theosophy was considered by Aleister Crowley to be a natural cousin of his philosophy, Thelema.
Crowley recognized Blavatsky as a Sister of the A\A\[...] specifically pointing her out as his immediate predecessor in "The Temple of Truth," published in The Heart of the Master through O.T.O. in 1938. He thought it especially noteworthy that he was born in the same year that the Theosophical Society was inaugurated. Crowley reissued Blavatsky's Voice of the Silence (Extracts from the Book of the Golden Precepts, including "The Two Paths" and "The Seven Portals") with his own commentary as Liber LXXI, a Class B publication of A\A\.
While Crowley boasted that O.T.O. was "the first of the great Old Aeon orders to accept the Law of Thelema," he evidently hoped that the Theosophical Society might be the second. In his Confessions, he claimed that the publication of Liber LXXI in the eleventh number of The Equinox was intended "to bring back Theosophists to the true principles of their founder."
With Theo Van Doesburg, Mondrian founded the Dutch movement called De Stijl.
So, I'm going to eat some cheese and listen to the White Stripes album of the same name. I deserve it after Six Degrees of Separationing Jack White and Aleister Crowley in only four steps.