- Location
- Mid-Atlantic
To make matters even more awkward, the "slaves see none of the rewards of their labor" argument isn't even universally true of Roman slavery; it depended on the precise terms and conditions of servitude imposed by circumstances.As pointed out, we're going to be hard pressed to push an economic angle since - as pointed out by Simon_Jester - the system of the time means that slavery may in fact be the genuinely most economically viable option for some tasks. To really push anti-slavery from an Economic angle, we both have to ensure that we've established a philosophic groundwork to argue that free men are going to do better work than slaves because free men reap the rewards of their own work while slaves see none of the rewards of their labor; and then ensure that we have a means to provide viable economic compensation to entice people to do jobs that nobody wants to do in a way that that's doesn't make that economic angle unviable for what we're getting.
A slave in a Roman mine wasn't going to benefit much from anything he did. A slave who had useful skills? Different kettle of fish, potentially.