Wright is best known for his publication An original theory or new hypothesis of the Universe (1750), in which he explains the appearance of the Milky Way as "an optical effect due to our immersion in what locally approximates to a flat layer of stars." This idea was taken up and elaborated by Immanuel Kant in his Universal Natural History and Theory of Heaven. Another of Thomas Wright's ideas, which is also often attributed to Kant, was that many faint nebulae are actually incredibly distant galaxies. Thomas Wright wrote:
..the many cloudy spots, just perceivable by us, as far without our Starry regions, in which tho' visibly luminous spaces, no one star or particular constituent body can possibly be distinguished; those in all likelihood may be external creation, bordering upon the known one, too remote for even our telescopes to reach.
Wright emphasised that Earth and the human race are insignificant and transitory parts of a vast universe:
In this great Celestial Creation, the Catastrophy of a World, such as ours, or even the total Dissolution of a System of Worlds, may possibly be no more to the great Author of Nature, than the most common Accident in Life with us, and in all Probability such final and general DoomsDays may be as frequent there, as even Birth-Days or Mortality with us upon this Earth.
Wright has been credited with work for William Capel, 3rd Earl of Essex at Cassiobury Park, illustrating his designs in 'A Walk in Cassiobury Gardens' and 'Views of Cassiobury'. In 'Grotesque Architecture' of 1767 there is a design for a rockwork bridge to decorate 'the fine piece of water' he had 'with great pleasure seen...at Cassiobury,; believed to be by Wright. A man of talents he also gave the Earl's daughters mathematical instruction. Another patron was Earl of Halifax at Horton House.
Thomas Wright was also credited with expanding the Grand Orrery to include Saturn.
^Thomas Wright, An Original Theory or New Hypothesis of the Universe … (London, England: H. Chapelle, 1750). From p.48: " … the stars are not infinitely dispersed and distributed in a promiscuous manner throughout all the mundane space, without order or design, … this phænomenon [is] no other than a certain effect arising from the observer's situation, … To a spectator placed in an indefinite space, … it [i.e., the Milky Way (Via Lactea)] [is] a vast ring of stars … "
Eileen Harris, ed., Arbours and Grottos. A facsimile of the two parts of Universal Architecture, (1755 and 1758), with a catalogue of Wright's works in architecture and garden design, London: Scolar Press, 1979.
University of Glasgow Library, Special CollectionsPlate VIII from Wright's 'An Original Theory or New Hypothesis of the Universe…': 'a proportional Drawing of all the primary and secondary Planets together, distinguished by their Characters...'.