The stance is very socialist/communist, I could easily imagine Lenin shown in the same pose. That’s not an accident. The statue is of Ferdinand Nieuwenhuis, and he was the first socialist elected to the Dutch parliament. He served as a member of the House of Representatives from 1888 to 1891, when he decided not to run again.
He began his professional life as a preacher, but gradually lost his faith and became increasingly socialist, “preaching” against the five K’s Kerk, Koning, Kapitaal, Kazerne en Kroeg (Church, King, Capital, Armed Forces and the Pub – yeah, it sounds better in Dutch). He fought for rights we now take for granted such as universal suffrage (which was granted in 1919 for men and women over 23 – the year of his death). He became increasingly anarchistic during his life, struggling with ideas of freedom and independence for all, he was both hated and loved in his time – with 12,000 people attending his funeral service in 1919.
There is a Ferdinand Nieuwenhuis museum , in Heerenveen (Friesland), which provides some information about his life, but all in Dutch.
Amsterdam doesn’t go in for fancy statues that much, and he stands on a forgotten corner of an intersection. But I’ll be paying a little more respect as I cycle past in the future.