From Butler’s Analogy (1765 edition, p. 158) here:
And the Appearances of Design and of final Causes in the Constitution of Nature, as really prove this acting Agent, to be an intelligent Designer, or to act from Choice; upon the Scheme of Necessity, supposed possible, as upon that of freedom.
Note: The author of 250 years ago follows the older practice of capitalizing all nouns; today, of course, only proper nouns (names) are capped. We don’t know if he “would have” capped “Designer.”
See also: “Intelligent design” goes back to 1766 (the contest for earliest reference to the term.)