at bottom

They concerted Matters, and all at once fell to selling off their Stock, giving out daily Reports that they would be no longer concern'd, that it was a losing Trade, that the Fund at bottom was good for nothing.

1705, Daniel Defoe, The Consolidator: or, Memoirs of Sundry Transactions From the World in the Moon

"Tess is queer." "But she's tractable at bottom. Leave her to me."

1891, Thomas Hardy, Tess of the d'Urbervilles, volume 1, London: James R. Osgood, McIlvaine and Co., page 45

At bottom I supposed that he had mistaken another book for mine.

1907 July 5, Mark Twain, chapter 23, in Chapters from My Autobiography

As the New Year opened, the survival of Western democracy rested, at bottom, on the case the U.S. would make for it.

1947 January 6, “The 80th Congress”, in Time, retrieved 26 Jun 2015

At bottom, he does not accept any authority higher than himself.

2015 June 20, Michael Lewis, “Harvard Admissions Needs ‘Moneyball for Life’”, in New York Times, retrieved 26 Jun 2015