A planned meeting between two Democratic presidential rivals collapsed Wednesday, with Jesse Jackson saying Albert Gore had launched an attack on him that was ``more personal than principled.'' Gore called Jackson's charge ``ridiculous'' and said he was merely holding his rival to the same standard as any other candidate. The two traded charges a day after Gore unleashed a broad assault on Jackson's record as without experience and said he was dismayed by Jackson's associations and Middle East policies. In his latest remarks, Gore defended his earlier criticism and said he had mentioned nothing that could be regarded as personal. ``There is no reason why anyone should think Jesse Jackson ought to be treated differently from any other candidate in this race,'' Gore told reporters. ``That's not a personal attack, and I'm surprised he would see it as a personal attack.'' ``I think it's ridiculous,'' Gore said. ``He's a major contender for the White House. Is he to be immune from any questioning of his position on the issues or his approach to the campaign? It's ridiculous.'' Gore commented at a news conference upon arriving in Washington from a campaign trip through New York and Wisconsin. Only moments earlier, Jackson had passed through the same private air charter terminal. The two had met on Monday and, according to both campaigns, agreed to set aside time Wednesday afternoon at National Airport for a meeting since their schedules coincided. But late Wednesday the meeting was canceled, the Gore campaign saying it was Jackson's move. Before departing on his own trip to Wisconsin, Jackson told reporters the two were planning to meet. But Jackson said that as a result of ``his attacks, which were more personal than principled, it's not necessary to meet at this time.'' Jackson said they would meet ``at some future time.'' Gore was informed of Jackson's comments and responded, questioning whether anyone believed he should ``bend over backwards to not say anything that might possibly be interpreted as critical'' of Jackson ``Is there supposed to be a separate standard?'' he asked. ``Is there supposed to be some unwritten rule why Jesse Jackson cannot be criticized, why his positions have to be just sancrosanct and nobody can say anything about them for fear somebody will just misinterpret what your saying? I have from the start of this campaign treated him exactly the same as every other candidate in this race.'' ``I don't think he really wants to be treated differently, and if he thinks about it he won't really see a criticism of his positions as a personal attack.'' Gore also took aim at Dukakis, the delegate leader who was considered the frontrunner for the nomination, at least until his massive loss to Jackson in Michigan last weekend. Gore faulted Dukakis for what he said was a refusal to even contrast himself with Jackson when asked. ``He was asked: `Why would you make a better president?''' Gore said of Dukakis. ``He said, `I'm not going to answer that question.' I think that's ludicrous.'' On Wednesday, however, Dukakis moved cautiously to contrast some of his positions with those of Jackson. He mentioned the Middle East and domestic policy as points of difference, but declined to provide specifics.