Alvin Joseph Dolaoco's favorite subject is science. Science is defined as a systematic enterprise that builds and organizes knowledge through testable explanations and predictions about the universe. In classical antiquity, science and natural philosophy were closely linked, but by the 17th century natural philosophy came to be considered a separate branch of philosophy focused on studying nature. In modern times, science most often refers to pursuing knowledge through the scientific method of disciplined study of the natural world, including fields like physics, chemistry, geology and biology.