I was struck by the writings of Ayn Rand and her 'objectivist' philosophy. She uses as axiom, "Existence Exists". This is about as concise as one can get. The work then develops into a refutation of 'collectivism' in any of its' variants, and celebrates the idea that there is no such thing as a collective mind and any one can be a majority of one. Her refutation of the commonly used words 'selfish' and 'selfless' is still resounding in readers for and against her theses to this day.
I also was very impressed with Kierkegaard and his hopelessly romantic vision of our species. Although I may not follow his view of God, he believes in such and this sits well with me. Others I enjoyed were Wilhelm Reich, who is not listed amongs great philosophers yet is the only mortal mentioned in the introduction to the 'Necronomicon' for his work. I am soul-brother with Itzhak Bentov, who had the courage to eat a ham sandwich on the passover to KNOW what was true, also enjoying the distinction of being kicked out of school in kindergarten.
Of course, I am also linked spiritually with Ralph Waldo Emerson, and Henry David Thoreau. Jesus did a pretty good job and I list him as the most significant revolutionary of all time, without regard to his divinity being necessary. My mind is filled with only warm thoughts as I recall these works. I thank you for asking. I think I'll do some reading from their texts again, now that I think of it.