My answer is the difference between government-controlled oligarchy versus private-sector oligarchy. Pick your poison.
Both void of rudimentary principles of the relativity theory of freedom, socialism becomes a government-controlled oligarchy, and capitalism becomes a private sector controlled oligarchy.
There is a future for a healthy blend of both, but only when subjugated to the freedom of freedom promulgated by evolution. The freedom of dissent that erodes oligarchies of aging merit.
