The book attempts to answer the question, "What is Life?" To do so, the author proposes considering all phenomena of Reality from two perspectives-both from the viewpoint of Metaphysical Realism and Anti-Realism. That is, the author asserts that Reality is twofold (dual), having two complementary sides-objective and subjective-and that relying on only one of these sides inevitably leads to an incomplete, one-sided understanding of things. Developing this approach, the author arrives at several non-obvious conclusions: that any Living entity is at least capable of understanding what Me is and can recognize the distinction between Me and Not-Me (a property of Subjectivity); that Life continuously improves due to the irresolvable dialectical contradiction between the subjective Me and the objective Not-Me (the Universe); that Life is hierarchical, consisting of levels; that cognition is only possible at a hierarchical level not higher than the given one; that for any living being, the event of Death only affects the outermost level of Life's hierarchy, while the lower levels may have a chance to survive, and so on. The book's most important conclusion is the assertion that there is no such thing as "living" and "non-living" Matter-all known and yet unknown elements of Matter are Subjective. Matter consists solely of an infinitely large ensemble of hierarchically organized and evolving Subjective Entities interacting with one another. This conclusion forms the basis of a new paradigm, which the author calls the Paradigm of the Great Life. The book also explores possible approaches to interpreting various phenomena in physics (including quantum mechanics and astrophysics) within the framework of the Paradigm of the Great Life.