The Leonardo essay contains Pater's ..
Pater’s essays take up a two-sided idea of the Renaissance, both normative and subversive, celebrating canonical artist-heroes even while depicting them engaged in behavior that would have scandalized Victorian society. (For example, many of the male artists he studies, such as Michelangelo and Leonardo da Vinci, are romantically involved with other men.) His recurring strategy is to engage with a well-known author or artist in a way that seems to agree with conventional wisdom, pretending to fit in with accepted judgments while at the same time proposing his own audacious opinions. Most famously, he quotes Matthew Arnold approvingly in his preface to The Renaissance, only to overturn Arnold’s idea in the following clause:
and his essays on Leonardo da Vinci, ..
While his later writings would gain him wide-raging respect, it was in Walter Pater's early works that first gained him some notoriety. While essays such as 'Coleridge's Writings' and 'Leonardo da Vinci' were well received, 'Conclusion,' closing his collection entitled The Renaissance, was extremely controversial. The view that finding the rare moments of joy and ecstasy should be the purpose of life was considered by many to be counter to Christianity by subjugating Heaven to these mortal experiences. While Pater was reserved and even apologetic regarding the reception of this short essay, the views he expressed in it remained with him and were expressed in later writings, regardless of continued criticism.
Consider the fact that the most controversial essay in was written first. Artists such as Leonardo da Vinci were at least as widely respected in the mid 19th century as they are now. By connecting his philosophy with universally admired artists of old, Pater borrows from their credibility while avoiding offending more contemporary artists who might not agree with him.