Seneca on freedom

From Moral letters to Lucilius/Letter 51 (Kindle):

Fortune is fighting against me, and I shall not carry out her commands. I refuse to submit to the yoke; nay rather, I shake off the yoke that is upon me, – an act which demands even greater courage. The soul is not to be pampered; surrendering to pleasure means also surrendering to pain, surrendering to toil, surrendering to poverty. Both ambition and anger will wish to have the same rights over me as pleasure, and I shall be torn asunder, or rather pulled to pieces, amid all these conflicting passions. I have set freedom before my eyes; and I am striving for that reward. And what is freedom, you ask? It means not being a slave to any circumstance, to any constraint, to any chance; it means compelling Fortune to enter the lists on equal terms. And on the day when I know that I have the upper hand, her power will be naught.