"Imagine a world in which every single person on the planet is given free access to the sum of all human knowledge," says Jimmy Wales about his brainchild Wikipedia, the non-for-profit crowd-sourced online encyclopedia.   But as internet freedoms are besieged by mass surveillance, can his project survive?  In this episode of Head to Head, Mehdi Hasan questions Jimmy Wales, one of the world’s most renowned internet gurus, on his future plans, on whether Wikipedia is advancing or degrading our knowledge, and on whether liberty, privacy and security can coexist in an online era.  So, is the internet dumbing us down? Is Wikipedia the best thing since sliced bread? Can online freedom survive state surveillance?  Joining the discussion are Bob Ayres, a former NSA and CIA intelligence officer; Isabella Sankey, the director of policy at British human rights organisation, Liberty; Herman Chinery-Hesse, a Ghanaian internet entrepreneur and founder of one of Africa’s largest software companies; and Oliver Kamm, a British writer and journalist.