Just a reminder that there are various forms of what we call "socialism", and some forms have definitely shown that they can work quite well.
It's usually difficult to determine whether there's a benefit (or how great the benefit is), because people don't do scientifically rigorous studies of welfare programs. There aren't randomly assigned control groups who
don't receive the benefit, so there's no comparison between the the people who receive it, and equally positioned people who don't.
Interestingly, someone actually managed to uncover some evidence (nearly a century old), that had an unintentional control group. The Mother's Pension Program (1911-1935) didn't have enough money for every applicant ... so the recipients were chosen in a somewhat random fashion. (Not scientifically random, but a large number of administrators were permitted to make choices in an arbitrary manner. On the whole the recipients and non-recipients were nearly identical.)
This inadvertently created a situation where there was a control group, and there is longitudinal data determining the life-long outcome for the recipients ... and the non-recipients.
Details of the program:
Under the program, a mother would receive
$15 per month for the first child, and
$5 per month for each additional child. Adjusting for inflation (1913 to 2014), that's equivalent to
$360 per month and
$120 per month. On
average, recipients were on the program for
3 years.
Outcomes:
On average, children who were part of the program stayed in school
a half year longer and earned
15% more as young adults. On average they also lived
1 year longer.
This suggests that at certain levels, socialistic welfare produces a benefit to society on any measure. The amount paid in is less than the amount eventually recovered in additional tax money from the recipients.
Sources:
Study Shows Long-Term Benefits Of Welfare Program : NPR
Washington State Historical Society > Mothers' Pensions
CPI Inflation Calculator