- Whenever two people A and B engage in a voluntary exchange, they must both expect to profit from it.
True a priori, as by definition one would not engage in the exchnage voluntarily unless one valued the good gained more than the good lost.
- Whenever an exchange is not voluntary but coerced, one party profits at the expense of the other.
True a priori, as if the victim had valued the good he obtained more than he valued the good he lost, that would have been a voluntary exchange by definition, not a coerced exchange. Therefore, in a coerced exchange, it must be the case that the victim did not value the good obtained more than the good lost.
- Whenever [one person’s] supply of a good increases by one additional unit, provided each unit is regarded as of equal serviceability by a person, the value attached to this unit must decrease.
Not true a priori, as it depends on the value scale of the person in question. For example, a person could have nothing on their value scale but chickens. Hence, no matter how many chickens he accumulates, getting another chicken never drops below anything else on his value scale, because there is nothing else on his value scale. That said, in all normal circumstances, the law of diminishing marginal utiity is a highly probable a posteriori claim, as typically (I want to say always, but it’s still a posteriori) people do have several things on their value scales, such that when the top value is satisfied, what had been the second highest value moves into the first rank, and so another unit of the item that had been in the first rank become less valuable than it had been.
- Of two producers, if A is more productive in the production of two types of goods than is B, they can still engage in a mutually beneficial division of labor.
Add “provided that A is not equally good at producing both goods, and B is not equally good at producing both goods,” and that’s true a priori, since the only case in which there cannot be mutually benefical exchange is if neither party is better at producing any one thing than they are at producing anything else, as then neither party can outsource production of what they’re worst at to focus on what they’re best at.
- Whenever minimum wage laws are enforced that require wages to be higher than existing market wages, involuntary unemployment will result.
Add “provided demand is elastic from the market price to the fix” and this is true a priori (understanding that it need not be an absolute increase in unemployment, but only higher unemployment than otherwise would have existed), as fixing the price of X above the market price decreases quantity demanded and (eventually) increases quantity supplied, resulting in an unsold surplus.
- Whenever the quantity of money is increased while the demand for money to be held as cash reserve on hand is unchanged, the purchasing power of money will fall.
You can say a priori that if the supply of a goods increases, and quantity demanded remains unchanged, either the price will fall or there will be an unsold surplus, but I suppose the claim that the former will occur rather than the latter rests on the a posteriori knowledge that unfettered markets will tend to clear (i.e. unsold surplus won’t last long and the price will fall).
