In the ongoing human pursuit of scale and certainty, Royal Caribbean is reaching beyond the sea toward solid ground — nearing a deal to acquire roughly half of Sandals Resorts at a valuation exceeding $6 billion. The move reflects a broader instinct among travel empires to own more of the journey, binding the floating world of cruises to the rooted world of beachfront resorts. Whether this convergence of two hospitality philosophies creates something greater than the sum of its parts, or simply a more complicated balance sheet, remains the defining question of the moment.