The site says the pledge is a "moral commitment" not a "legal contract".

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The pledge is a moral commitment to give, not a legal contract, and it does not involve pooling money or supporting a particular set of causes or organizations.

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The Cuban artist's posters will also be displayed throughout central Cardiff, while visitors to the exhibition at the National Museum of Art will be invited to sign a 'moral commitment contract' promoting immigrants' rights.

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Some members of Congress believe deeply in the moral-commitment argument, but others are no doubt impressed by the sight of literally dozens of military organizations lobbying Capitol Hill to block the increase.

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Greater fiscal integration requires the upfront and ongoing commitment of voters and officials across member countries and increases the risk of moral hazard like free riding and breaking of covenants in the future, especially from member states that would be required to execute tough reforms.

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As a nation, we'll pledge to fulfill our responsibilities to our veterans, because our commitment to our veterans is a sacred trust, and upholding that trust is a moral obligation.

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