It is with joy that I answer your question. And if I may be allowed to answer it philosophically. The books you find incredibly interesting may be the books the validate your worldview. There are many of these. The book you find eye-opening may be the books that open the door into the world of philosophy proper for you. There are not many of these because you only need to go through that door once I feel.
Also, I would observe that besides Ayn Rand (who for many is not a philosopher) not a single female philosopher has been mentioned here which I find is a damning indictment on the state of affairs of the world of ideas. To remedy that I would recommend to you read A Vindication of the Rights of Woman by Mary Wollstonecraft or anything by De Beauvoir (and do ignore her contemporary Sartre for he was nothing but a windbag).
I am delighted that you singled out Thomas Paine (who again is not a philosopher as such; must be something in the air in the States) and Arthur Schopenhauer. They are both tremendous stylists. I've said this many times before - I don't care how great a philosopher's ideas are, if they can't write well I don't want to know. Thus we have people here recommending Kripke or Frege or heck knows who like that who bludgeon you to death with their tedious logic. Avoid them I say.
Finally I would like to be clichéd and recommend anything by Nietzsche except for Thus Spake Zarathustra even though he himself considered it his best work and I would especially recommend Ecce Homo by him because it is a summation of his previous works by his own hand. Nietzsche was the supreme stylist and ruthlessly honest and fearless. Also I'd recommend A Short Treatise on the Great Virtues by a contemporary philosopher André Comte-Sponville. This is a remarkable book on virtue theory that takes in Aristotle, Spinoza, Nietzsche and Woody Allen among others and is divided up by virtue which is extremely novel. It is fantastically written. Anything by Cioran as well such as The Trouble with Being Born. I'm trying not to typecast myself here! :)
And finally finally Sophie's World and The Art of Motorcycle Maintenance while nice cute books are not true philosophy books. This is also why I wouldn't recommend Camus' The Outsider though someone did mention The Myth of Sisyphus. Borges falls into this category. Sophie's world is really a kid's book as well and one that I would perhaps recommend to children though I'd recommend Borges or Camus or Kafka first.
Also, I would observe that besides Ayn Rand (who for many is not a philosopher) not a single female philosopher has been mentioned here which I find is a damning indictment on the state of affairs of the world of ideas. To remedy that I would recommend to you read A Vindication of the Rights of Woman by Mary Wollstonecraft or anything by De Beauvoir (and do ignore her contemporary Sartre for he was nothing but a windbag).
I am delighted that you singled out Thomas Paine (who again is not a philosopher as such; must be something in the air in the States) and Arthur Schopenhauer. They are both tremendous stylists. I've said this many times before - I don't care how great a philosopher's ideas are, if they can't write well I don't want to know. Thus we have people here recommending Kripke or Frege or heck knows who like that who bludgeon you to death with their tedious logic. Avoid them I say.
Finally I would like to be clichéd and recommend anything by Nietzsche except for Thus Spake Zarathustra even though he himself considered it his best work and I would especially recommend Ecce Homo by him because it is a summation of his previous works by his own hand. Nietzsche was the supreme stylist and ruthlessly honest and fearless. Also I'd recommend A Short Treatise on the Great Virtues by a contemporary philosopher André Comte-Sponville. This is a remarkable book on virtue theory that takes in Aristotle, Spinoza, Nietzsche and Woody Allen among others and is divided up by virtue which is extremely novel. It is fantastically written. Anything by Cioran as well such as The Trouble with Being Born. I'm trying not to typecast myself here! :)
And finally finally Sophie's World and The Art of Motorcycle Maintenance while nice cute books are not true philosophy books. This is also why I wouldn't recommend Camus' The Outsider though someone did mention The Myth of Sisyphus. Borges falls into this category. Sophie's world is really a kid's book as well and one that I would perhaps recommend to children though I'd recommend Borges or Camus or Kafka first.
http://www.amazon.co.uk/Vindication-Rights-Woman-Penguin-Cla...
http://www.amazon.co.uk/Second-Sex-Vintage-classics/dp/00997...
http://www.amazon.co.uk/Penguin-Great-Ideas-Suffering-World/...
http://www.amazon.co.uk/Ecce-Homo-Becomes-Penguin-Classics/d...
http://www.amazon.co.uk/Short-Treatise-Great-Virtues-Philoso...
http://www.amazon.co.uk/Trouble-Being-Born-E-M-Cioran/dp/155...