[piva00]

> Labor by itself produces no value. Roll a rock up and down a hill and no value is created.

The statement isn't that all labour produces value but that labour is the source of all value. Without labour there's absolutely no way to provide value.

I'd like to know an example of something that produces value without labour, I really cannot come up with one.

[s1artibartfast]

Being a requirement is different than the source. It is a component and an input. You can have multiple inputs that each are necessary but not sufficient. The issue arises in describing something as the sole cause or source.

Humans need to Air to breath. Air is the source of all life. Humans need water to drink. Water is the source of all life. Humans need food to eat. Food is the source of all life.

The reality is that humans need all these things and more to live. None of them are sufficient for life by themselves.

The same is true of labor.

[JumpCrisscross]

> I'd like to know an example of something that produces value without labour

A painting by a long-dead artist. That’s what I meant by “amortising past labour across [the] future.” (I phrased it badly originally.)

Also, natural resources. The total value of a chopped-down tree is well in excess of the labour used to chop it down.

[piva00]

> A painting by a long-dead artist. That’s what I meant by “amortising past labour across [the] future.” (I phrased it badly originally.)

Thanks for elucidating it, I understand your point better.

Then again, the source of value came from labour. The long-dead artist had to put on labour not only for that single piece of painting but across a whole body of work for that painting to appraise in value over time, the scarcity drives its value further but it was from labour the value originated and grew from, both the actual work done for that painting as the whole life of the artist to become a valuable object.

> Also, natural resources. The total value of a chopped-down tree is well in excess of the labour used to chop it down.

Without the labour to chop the tree down it doesn't have inherent value, through labour it's transformed and more wealth is created since a natural resource after processing is more useful. It does not detract from my point that without labour there would be no exchangeable value/trade to extract surplus value since the material would not exist, the source of wealth creation is labour.

[s1artibartfast]

IMO, the whole concept of "value" is useless when unmoored from the appraiser. Value is subjective. Something can have different value to the buyer and seller, and in fact there must be a difference in value for transactions to occur.

Whose labor is responsible for the market value of the wood. Is it the planter, the cutter, or hauler, and in what proportions? All are necessary, none are sufficient. The only way to have a meaningful assessment of "labor value" is in the the prevailing price in a labor market.