"Increasing the size of the workforce will tend to put downward pressure on wages."
I am also not an economist, but you're only covering the supply of workers. Do more workers = more money being spent = more products/services demanded = increased demand for workers? In other words, does it even out?
I have read that wages have decreased in the last few generations while dual income houses became normal, but I don't know whether those are cause and effect or have common causes.
I'm not an economist either, but heuristically I'd expect the precise opposite to be true: the products/services with elastic demand curves (that is, luxuries) tend to require time to consume in addition to money. Simply having more money available will not necessarily increase demand for these things.
If you wanted to make this argument, I think a better way to approach it would be from the supply side. The supply of goods and services should increase, because well, that's what workers produce. This should theoretically lower the prices of existing goods and services, because increased supply of a commodity puts downward pressure on pricing.
That's all in theory. I highly doubt it's anywhere near that simple. The thing about macroeconomics is that it's somewhere between cargo cultism and ancient mythology: people compare situations that superficially resemble each other, and then invent models that explain several situations but are entirely untestable.
I am also not an economist, but you're only covering the supply of workers. Do more workers = more money being spent = more products/services demanded = increased demand for workers? In other words, does it even out?
I have read that wages have decreased in the last few generations while dual income houses became normal, but I don't know whether those are cause and effect or have common causes.