
Sen was originally motivated to study economics when, as a boy, he lived through one of India's famines while working at a grain/rice/? silo. He wanted to reconcile the fact that there was a large amount of excess grain left at the time the next crop was being harvested with the fact that he had seen starved corpses along the streets (and had heard that the famine was much worse elsewhere through the newspaper). He eventually came to the conclusion that the famine he had lived through, along with many others, was primarily economic (due to inequality combined with a few other triggers) rather than due to local food supply actually falling below what was needed to feed the population.
I don't know as much about Picketty (I had Sen as a lecturer -- didn't care much for him in that capacity, but his writing was top quality). I do know that I haven't been impressed or convinced by Picketty's arguments, which read as if they were written by someone who had never read Sen's book (he keeps raising objections that Sen thoroughly addressed >30 years ago).
That doesn't follow. It's quite possible to simultaneously have
1. Capacity to produce plenty of available food, land, shelter, etc
2. Plenty of people willing to work for the food, land, and shelter
3. Lack of fed and sheltered people due to #2's labor having lower value than #1
There is no reason why the market determined value of labor (VOL) must exceed the market determined cost of living (COL). It happens. This is what people mean when they say that famine is a distribution problem, not a production problem. What they really mean is that it's an economic problem. Markets are entirely compatible with the notion of an underclass that cannot put food on the table, even amid abundance. Refer to the (e)book "Poverty and Famines" by Amartya Sen for examples and analysis. Exporting food while part of the populace starves isn't a stunt reserved for communist countries.
Thought experiment: there's a village with 100 peasants and surrounding land capable of producing 100 units of food if tended to by 75 laborers. The landowner hires 75 laborers, providing them each with 1 unit of food in return (supply of labor exceeds demand, so he has all the bargaining power). He sells the remaining 23 units at market in the neighboring town.
What do the 25 peasants that weren't needed do? Go to the neighboring town? What if nobody there is hiring either?
> That fact that we cannot provide a high enough average standard of living even when the incentive to work is very high, proves that drastically lowering the incentive to work would not provide a sufficient standard of living.
A high standard of living requires more than products of labor. Crucially, it requires control over resources. The market provides sufficient indirect control if VOL>COL. We can empirically and theoretically observe that that's not always the case.
[edit] I believe the book is Poverty and Famines: An Essay on Entitlement and Deprivation.
http://www.worldcat.org/title/poverty-and-famines-an-essay-o...
Regarding economics as a science, it is widely accepted by economists that it is not a precise science, and has no inviolable axioms like math, or anywhere approaching the experimental accuracy of physics. It is a messy, complicated thing because humans are messy and complicated. In particular, it is well established through the works of people like Kahneman than people are not rational actors.
In addition, you seem to be resorting to a false dichotomy between capitalism as it exists today vs command economies. You don't have to choose one or the other. Markets are certainly an important and useful way of distributing resources, but they are dominated and controlled by a small, powerful, capitalist class, who are also able to abuse regulatory institutions for their own benefit. The problem is that this class appropriates wealth created by society at large. They have the power to set up rules and conditions in their own favor.
Any "just" and "fair" system could only begin by returning this wealth back to society.
The "sooner or later" argument is that of "Limits to Growth"; we're not there yet.