“Thank you for acceding to our request,” it said, after our computers established a linguistic link. “I represent the intergalactic Corps of Obligate Pragmatism.”

We had never heard of the institution, but the Captain replied with aplomb.

“You don’t say? And what can we do for you?”

“You can accommodate us by engaging in a discussion concerning your star drive.”

“Yes? And what about our star drive?”

“It operates by the series-implosion of micro-singularities, which you create by borrowing space-time-metric, using principals of quantum uncertainty. Before this borrowed debit comes due, you allow the singularities to re-collapse behind you. This creates a spacetime ripple, a wake that propels you ahead without any need on your part to expend matter or energy.”

I could not have summarized it better to my students.

“Yes?” The Captain asked succinctly. “So?”

“This drive enables you to travel swiftly, in relativistic terms, from star system to star system.”

“It has proved rather useful. We use it quite extensively.”

“Indeed, that is the problem,” answered the wispy star probe. “I have chased you across vast distances in order to ask you to stop.”

No wonder it had used such a strange method to catch up with us! The COP agent claimed that our BHG drive was immoral, unethical, and dangerous!

“There are alternatives,” it stressed. “You can travel as I do, pushed by intense beams cast from your point of origin. Naturally, in that case you would have to discard your corporeal bodies and go about as software entities. I contain about a million such passengers, and will happily make room for your ship’s company, if you wish to take up the offer of a free ride.”