"When it aims to express a love of the world it refuses to conceal the many reasons why the world is hard to love, though we must love it because we have no other, and to fail to love it is not to exist at all"

Mark Van Doren's quote is a reflection on the complex relationship humans have with the world-- a relationship that is tinged with both beauty and hardship. The opening phrase, "When it intends to express a love of the world", recommends a goal or undertaking to welcome the world in its entirety. This shows a mindful choice or effort to cultivate a gratitude for life and existence, acknowledging that such love is not born of naivety however of a deliberate recognition of reality.

The subsequent clause, "it declines to conceal the many reasons why the world is tough to like", discovers the fundamental duality of life's experiences. It underscores the idea that an authentic love for the world does not shy away from acknowledging its imperfections, obstacles, and the suffering that is woven into the human experience. The world is complicated, filled with moments that can be extremely tough to fix up with the perfect of love. There are oppressions, discomforts, and tragedies that make complex the easy notion of love.

"Though we should enjoy it because we have no other", presents a sense of inevitability and necessity. Here, Van Doren suggests that in spite of the bitterness and challenges, there is a compulsion to like the world because it is, ultimately, our only alternative. This isn't simply a physical exclusivity, but an existential one; the world offers the canvas upon which we paint our lives-- it's our home, with all its flaws and splendor.

Lastly, "to fail to enjoy it is not to exist at all", posits an existential claim that love and existence are intertwined. To reject the world in its totality would indicate to decline life itself. Through this lens, love ends up being a basic part of existence. It is not simply recommended however vital for a significant life. Thus, by acknowledging the difficulties and dedicating to enjoy the world anyway, people verify their participation in, and acceptance of, the really act of living.