Owen Jones says: "As a socialist, I am compelled to have an optimistic view of humanity, to believe we are not all motivated by greed, selfishness or hate." I have problems with this.

First, the way Owen puts this, it looks like wishful thinking; his view of an objective fact (human nature) is motivated by political beliefs. This is surely irrational.Human nature is what it is, whether you're a socialist or not.

My bigger gripe, though, is that I'm not sure such idealism is necessary for socialism at all.

Put it this way. Owen is surely right to say that the Holocaust - and I'd add much else in history - shows the "almost infinite malleability of humanity": we are capable of great evil and great good.

The question, therefore, for socialists and everyone else is: through what mechanisms and institutions is behaviour shaped? Could socialistic institutions generate more good behaviour and less bad than capitalistic ones? There are (at least) three reasons to think so:

1. We know from the orthodox economics of crime and from Ben Friedman's historical research that people who are fearful, poor and insecure tend to behave worse than those who are not. This suggests that egalitarian institutions should reduce crime and violence, and perhaps intolerance generally.

2. Hierarchical companies have (built-in?) adverse selection mechanisms; their leaders are selected to be irrational, narcissists or psychopaths. And market forces might not select against companies run by such people.

Of course, the problem here is not capitalism but any hierarchy: Stalin's USSR and Fred Goodwin's RBS both demonstrate my point. It is for this reason that socialism must be non-hierarchical.

3.There's reasonable evidence that worker-managed firms are at least (pdf) as efficient as similar (pdf) capitalistic ones, perhaps because peer pressure helps boost productivity. This suggests that egalitarian institutions can restrain our selfish impulses to be lazy whilst others do the work.

In these respects, socialism - which is not the same as statism, mad libertarians please note - has the edge.

The big open question, however, concerns the role of markets. You could interpret these as a fantastic mechanism for converting selfish impulses into social benefits, as Smith did when he said "it is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own interest."

On the other hand, though, we know that the cash incentives used by markets can crowd out intrinsic motives and creativity so that selfishness is economically inefficient.

My point here is not to cheer for socialism, or to make sweeping generalizations. Instead, it is merely to suggest that socialism - for me anyway! - is not about hippy-dippy all-you-need-is love idealism, nor about emoting about "unfair" capitalism. Instead, it is question about the interplay of institutions and behaviour.