Basically, I suppose the justification for studying these lattice models is very simple: they are relevant and they can be solved, so why not do so and see what they tell us?
R.J. Baxter, Exactly Solved Models in Statistical Mechanics (Academic Press, 1982)

I got really fascinated by these (1+1)-dimensional models that are solved by the Bethe Ansatz and how mysteriously they jump out at you and work and you don't know why. I am trying to understand all this better.
Richard Feynman (1988)

Mathematics is the tool specially suited for dealing with abstract concepts of any kind and there is no limit to its power in this field.
P.A.M. Dirac, The principles of Quantum Mechanics (Oxford, 1930)

I shall conquer this. I shall.
Mr Darcy, Pride and Prejudice

Look at this place. It's full of rich men and any one of them could write his name across it forever by bequeathing it a public monument or institution, or endowing scholarship or the arts. But they carry money-grubbing into the grave with them, and rot there forgotten, as they damn well deserve to be.
J F Archibald to Norman Lindsay looking out towards Sydney from the steps of the NSW Art Gallery, in My Mask by Norman Lindsay (1970)