Book excerpt: The Natural Philosophy Alliance (NPA) sponsors regular international conferences for presenting high-quality papers discussing aspects of philosophy in the sciences. Many papers offer challenges to accepted orthodoxy in the sciences, especially in physics. Everything from the micro-physics of quantum mechanics to the macro-physics of cosmology is entertained.Though the main interest of the NPA is in challenging orthodoxy in the sciences, it will also feature papers defending such orthodoxy. Our ultimate propose is to enable participants to articulate their own understanding of the truth. All papers are reviewed by society officers, and sometimes by other members, before presentation in conferences and they are edit, sometimes very significantly prior to publication in the Proceedings of the NPA.