Now I admit at once that the interest in the Beautiful of Art (under which I include the artificial use of natural beauties for adornment and so for vanity) furnishes no proof whatever of a disposition attached to the morally good or even inclined thereto. But on the other hand, I maintain that to take an immediate interest in the Beauty of Nature (not merely to have taste in judging it) is always a mark of a good soul; and that when this interest is habitual it at least indicates a frame of mind favourable to the moral feeling, if it is voluntarily bound up with the contemplation of nature. It is to be remembered, however, that I here speak strictly of the beautiful forms of Nature, and I set aside the charms, that she is wont to combine so abundantly with them; because, though the interest in the latter is indeed immediate, it is only empirical.
He who by himself (and without any design of communicating his observations to others) regards the beautiful figure of a wild flower, a bird, an insect, etc., with admiration and love—who would not willingly miss it in Nature, although it may bring him some hurt, who still less wants any advantage from it—he takes an immediate and also an intellectual interest in the beauty of Nature. I.e. it is not merely the form of the product of nature which pleases him, but its very presence pleases him, the charms of sense having no share in this pleasure and no purpose whatever being combined with it.
Jane Austen, Mansfield Park, Chapter 22;
Miss Crawford, untouched and inattentive, had nothing to say; and Fanny, perceiving it, brought back her own mind to what she thought must interest.
"It may seem impertinent in me to praise, but I must admire the taste Mrs. Grant has shewn in all this. There is such a quiet simplicity in the plan of the walk! Not too much attempted!"
"Yes," replied Miss Crawford carelessly, "it does very well for a place of this sort. One does not think of extent here; and between ourselves, till I came to Mansfield, I had not imagined a country parson ever aspired to a shrubbery, or anything of the kind."
"I am so glad to see the evergreens thrive!" said Fanny, in reply. "My uncle's gardener always says the soil here is better than his own, and so it appears from the growth of the laurels and evergreens in general. The evergreen! How beautiful, how welcome, how wonderful the evergreen! When one thinks of it, how astonishing a variety of nature! In some countries we know the tree that sheds its leaf is the variety, but that does not make it less amazing that the same soil and the same sun should nurture plants differing in the first rule and law of their existence. You will think me rhapsodising; but when I am out of doors, especially when I am sitting out of doors, I am very apt to get into this sort of wondering strain. One cannot fix one's eyes on the commonest natural production without finding food for a rambling fancy."
"To say the truth," replied Miss Crawford, "I am something like the famous Doge at the court of Lewis XIV.; and may declare that I see no wonder in this shrubbery equal to seeing myself in it. If anybody had told me a year ago that this place would be my home, that I should be spending month after month here, as I have done, I certainly should not have believed them. I have now been here nearly five months; and, moreover, the quietest five months I ever passed."
(The Doge of Genoa, asked what he thought most wonderful about Versailles after visiting in order to beg Louis XIV for peace, responded, "To see myself here." It was an answer that the French could hardly avoid celebrating, even in a humiliated enemy. Or, given that we are talking about early modern France, perhaps especially in a humiliated enemy.)
The liking for natural beauty is indeed related to a moral disposition in Austen; and liking for the beautiful in art is at least more ambiguous. We get something like this in MP, since Fanny's preference for the natural, contrasted with the preference for the artificial in some of the other characters (as seen in the earlier scene when everyone discusses 'improvements'), is an indication of character.
There is an old idea that the virtue of temperance involves a love for the beauty of restraint and proportion; so that it should have at least an analogy, and perhaps a shared foundation, with love for natural beauty makes a certain amount of sense. It's certainly the case that the link between the two comes up again and again in the history of the subject.