"I see no adequate reason for refusing the franchise to any sane self-supporting adult otherwise eligible, on the score of her sex alone."
I'd never heard of Henry Sidgwick before today. He was a nineteenth century learned gentleman, and campaigner for women's access to university. I doubt he idenitified as a feminist, but I'm glad to recognise him for the work he did for women's rights. He didn't just set up a college for women, he resigned from one of his roles in protest of Cambridge refusing to give degrees to women. That's the action that earns my respect, when men give up some of their power and privilege I start to take them seriously (particuarly when it actually has some affect - it's not just an attention gathering/self pity exercise).
Fights for women's rights in the nineteenth century - particularly issues like access to university - can be easy to dismiss. They seem so remote, and they don't seem to have made that much difference, so it's quite easy to forget how important they were. The basic rights had to be fought for, even if gaining them didn't make that much difference, because it's one less thing that we have to fight for now, it shows us what might make a difference, and it gives us a place to stand.
He seems to have been a bit of a grumpy old codger as well - not providing greek and latin at his college - not because he thought that these ancient languages would ruin women's uteruses (you have to wonder how the original greeks and romans reproduced), but because he thought that degrees for men placed too much importance on dead languages. He wasn't above a discipline fight in his principled crusade, and I find that amusing.
It does raise a wider question about whether men can be feminists. Which I have to admit I've always found a bit academic, because I've never really known a man who wanted to be. Despite moving in activist circles I've never known, in person, a man who prioritises feminism in their work. I'm sure they exist (I suspect Barry from Amptoons is one), but until I meet them it seems like a pointless argument. The best I can say for the guys that I know, is that some of them want to fight to make this a better place for women, but they don't want it enough that they actually find a way to be part of the fight.
Conclusion: I doubt Henry called himself a feminist - but he seems kind of cool - better than Maggie anyway.