Of course dollars matter when they come out of the mattress. But the issue was what happens in the short term if they are kept there and not spent. The amount

Of course dollars matter when they come out of the mattress. But the issue was what happens in the short term if they are kept there and not spent. The amount of resources in the world available for either consumption or investment (future consumption) don't change when a bubble is collapsing. Resources are just more likely to be used to grow sound businesses. And that creates more resources and good jobs in the future. Consumers curtail their consumption because they are no longer fooled into thinking that their wages and asset rices will be rising fast. They stop loading up on debt. They aren't bidding up prices and the factors of production are cheaper as a result, helping expand businesses that do make sense.