Tibet's exiled spiritual leader, the Dalai Lama, says he is trying to keep the focus of his trip to Washington on scientific, not political, matters.  He spoke Tuesday before the opening of a three-day conference that examines how meditation affects mental and physical health.  

At a meeting with reporters before the start of the conference, the Dalai Lama was asked only one question about China.  The Tibetan spiritual leader gave a brief answer, saying that although the Tibetan government in exile and Beijing have been in direct contact, he hasn't seen improvements on the ground, inside Tibet.

"So far, [there has been] no such sign," he said.  "Still, things are very, very repressive." 

He said most of his time during his 10 day visit to Washington is devoted to science, including this week's conference, titled "The Science and Clinical Applications of Meditation."

In his opening remarks to the gathering, the Dalai Lama said Buddhists and scientists have something in common -- they both seek to dispel ignorance with knowledge, gained from experimentation and investigation. 

"So, science and Buddhists, I think both are actually trying to find reality," the Dalai Lama said.

The conference's main sponsor is the Mind and Life Institute, a non-profit organization that promotes dialogue between modern science and contemplative traditions, such as Tibetan Buddhism. 

Mind and Life Institute chairman Adam Engle compared meditation to exercise, saying a healthy mind is as important as a healthy body.

"So, in the same way that you've got a myriad of physical exercises to help your body, there are a myriad of mental trainings.  And this is not well known.  Most people, when they think about meditation, they think about turning your body into a pretzel and zoning out somewhere," he said.  "But it is really just a word for mental training."

These ideas were given weight by the meeting's co-sponsors, Georgetown University Medical Center and the Johns Hopkins University School of Medicine.

Not all scientists agree with the Dalai Lama, though.  More than 500 brain researchers signed a petition urging the Society for Neuroscience to cancel his lecture to the group's annual meeting.  Many of those who signed the petition believe the field of neuroscience risks losing credibility if it mixes science with spirituality.

Meantime, the Dalai Lama also commented on a vexing issue in the United States -- namely the origin of human beings.  He said some Buddhist scriptures say humans descended from higher beings.  But he added that the traditional Tibetan myth of creation says humans descended from monkeys.

"I don't know, all human beings or not.  At least Tibetan human beings come from monkeys," he said. "So, that's more scientific." 

On non-scientific matters, the Dalai Lama meets with congressional leaders.  He also is expected to meet at the White House with President Bush, who is traveling to China later this month. 

The Dalai Lama is the head of Tibetan Buddhism.  He has lived outside of Tibet since fleeing in 1959.  His remote Himalayan homeland is inside China, which  accuses the Dalai Lama of undermining national unity and trying to gain international support for Tibetan independence.