The universality of mesoscales, ranging between elemental particles and the
universe, is discussed here by reviewing widely disparate fields and presenting
four cases, at differing hierarchical levels, from chemistry, chemical
engineering, meteorology, through to astronomy. An underpinning concept,
"Compromise in competition", is highlighted between various dominant, but
competing mechanisms, and is identified here to be the universal origin of
complexity and diversity in such examples. We therefore advance this as a key
underlying principle of an emerging science -- Mesoscience.Comment: 8 pages, 1 figur