C.D. Broad wrote an article that differentiated between critical/analytic philosophy and speculative/metaphysical philosophy. Critical philosophy involves analyzing and defining concepts and critically examining beliefs, while speculative philosophy aims to understand the nature of the universe and humanity's place in it. Reductionism breaks things down into constituent parts, while holism sees the whole as greater than the sum of its parts. Holism argues that a system's properties depend on interactions rather than individual parts.