How does the book demonstrate feminism?

Modern feminists see Jane Eyre as one of the first feminist novels. In her biography of Brontë, entitled The Brontë s: Charlotte Brontë and Her Family, Rebecca Fraser remarks that it was "Charlotte's protest against the stifling convention society imposed, which never allowed true feeling to be voiced." However, Scargill notes that "Jane Eyre may speak for women, but it speaks also for all humanity..."