Definition of "thankfulness"

All our Diſcontents about what we want, appeared to me, to ſpring from the want of Thankfulneſs for what we have.

1719 May 6 (Gregorian calendar), [Daniel Defoe], The Life and Strange Surprizing Adventures of Robinson Crusoe, […], 3rd edition, London: […] W[illiam] Taylor […], published 1719, page 153

No matter how early I came down, I would find him on the veranda, smoking cigarettes, or […] . And at last I began to realize in my harassed soul that all elusion was futile, and to take such holidays as I could get, when he was off with a girl, in a spirit of thankfulness.

1897 December (indicated as 1898), Winston Churchill, chapter IV, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd., page 46

King's Messenger, 1918-1940: Memoirs of a Silver Greyhound. By George P. Antrobus, O.B.E., King's Foreign Service Messenger 1918-1940. London: Herbert Jenkins Ltd. Price 10s. 6d. net. [...] There is cause for thankfulness that he had just completed this book before he died, for it is a worthy memorial.

1941 October, “Railway Literature”, in Railway Magazine, page 480