Investment in science is a pillar for any dynamic, equitable modern society, and promoting scientific literacy across all levels of society can help foster innovation, dialogue, and consensus that crosses disciplinary and cultural boundaries. Science also helps to uncover answers to foundational questions that have captivated, confounded, and divided our species for millennia. But what is “science,” and what kind of “evidence” ensures that an approach is scientific? If we take “science” to broadly mean, in its purest sense, a “dynamic search for the truth,” or more explicitly, “the pursuit and application of knowledge and understanding of the natural and social world following a systematic methodology based on evidence,” as the Science Council aptly defines it, then science extends beyond the established, highly specialized disciplines of reductionist natural sciences (physics, chemistry, biology, geoscience, and space science) that have been so successful in fostering our understanding of our planet and the cosmos. Under this definition, science also includes the rigorous data-driven (qualitative and quantitative) social sciences, the inherently non-reductionist “holistic” sciences such as ecological and Earth system sciences, and the budding interdisciplinary field of complex systems science, as well as robust traditional knowledge systems based on multi-generational experiences, observations, and reasoning. As with science, “evidence” can mean a lot of things as well, including primary research, pre-existing data, past and planned experiments, and the referencing of peer-reviewed publications and primary sources. It can also include local and traditional knowledge, thought experiments, theoretical proofs, contemplation, verifiable personal experience, and empirical observation. Broadening and weaving together these forms of scientific evidence holds the potential to address complex, interconnected global challenges and explain deep mysteries that could help unify our polarized societies around foundational understandings. Foundational Questions Foundational questions can transcend the divides of generations and cultures: Cosmology, physics, and evolutionary biology have shed...