From, Dombey & Son, by Charles Dickens (via Gutenberg), Chapter 8:
“…. ‘Papa! what’s money?’
The abrupt question had such immediate reference to the subject of Mr Dombey’s thoughts, that Mr Dombey was quite disconcerted.
‘What is money, Paul?’ he answered. ‘Money?’
‘Yes,’ said the child, laying his hands upon the elbows of his little chair, and turning the old face up towards Mr Dombey’s; ‘what is money?’
Mr Dombey was in a difficulty. He would have liked to give him some explanation involving the terms circulating-medium, currency, depreciation of currency’, paper, bullion, rates of exchange, value of precious metals in the market, and so forth; but looking down at the little chair, and seeing what a long way down it was, he answered: ‘Gold, and silver, and copper. Guineas, shillings, half-pence. You know what they are?’
‘Oh yes, I know what they are,’ said Paul. ‘I don’t mean that, Papa. I mean what’s money after all?’
Heaven and Earth, how old his face was as he turned it up again towards his father’s!
‘What is money after all!’ said Mr Dombey, backing his chair a little, that he might the better gaze in sheer amazement at the presumptuous atom that propounded such an inquiry.
‘I mean, Papa, what can it do?’ returned Paul, folding his arms (they were hardly long enough to fold), and looking at the fire, and up at him, and at the fire, and up at him again.
Mr Dombey drew his chair back to its former place, and patted him on the head. ‘You’ll know better by-and-by, my man,’ he said. ‘Money, Paul, can do anything.’ He took hold of the little hand, and beat it softly against one of his own, as he said so.
But Paul got his hand free as soon as he could; and rubbing it gently to and fro on the elbow of his chair, as if his wit were in the palm, and he were sharpening it—and looking at the fire again, as though the fire had been his adviser and prompter—repeated, after a short pause:
‘Yes. Anything—almost,’ said Mr Dombey.
‘Anything means everything, don’t it, Papa?’ asked his son: not observing, or possibly not understanding, the qualification.
‘It includes it: yes,’ said Mr Dombey.
‘Why didn’t money save me my Mama?’ returned the child. ‘It isn’t cruel, is it?’
‘Cruel!’ said Mr Dombey, settling his neckcloth, and seeming to resent the idea. ‘No. A good thing can’t be cruel.’
‘If it’s a good thing, and can do anything,’ said the little fellow, thoughtfully, as he looked back at the fire, ‘I wonder why it didn’t save me my Mama.’”
You can read Dombey and Son at Gutenberg dot org and you can find this excerpt there by “finding” (CTRL-F) the words: what is money. This excerpt is in: CHAPTER 8. Paul’s Further Progress, Growth and Character.