Since it was him who brought up the analogy of the Titanic and compared this "system of things" to a sinking ship, you could say;
"Not assisting the needy today simply because one believes this system is doomed, is the equivalent of the Titanic's crew not distributing the ships life preservers to their passengers since they'd only survive for a short time in the icy water anyway. Only the most heartless of crewman would reason such a thing. On the other hand a caring and responsible crewman would offer whatever assistance he could. He'd realize that the life preservers although inadequate, will go down with the ship if they aren't used and it's worth a shot to use every last one of them, even if only to make the passengers a little warmer as they waited to enter the water. Likewise, the same could be said of the material goods of this world. If this system is indeed going down, as you say it surely is, the humane thing to do is to help make as many people as comfortable as possible for as long as possible, in any way we can".
Of course any JW worth his salt will tell you that for the good of the greater number, It's better to spend our efforts warning approaching ships about the Iceberg rather than waste time on the one already sinking into the water.
To that I'd say:
The system of things in your analogy is one big sinking ship. There are no other approaching ships in this story. Besides, why not do both? How long would it take for a crew of men to hand out a few hundred life jackets while one or two of them sounded the alarm and radioed a warning to nearby ships?
