Clarke's Second Law

"Any sufficiently advanced technology is indistinguishable from magic."
- Arthur C. Clarke.

Corollaries:

"Any sufficiently advanced magic is indistinguishable from technology."
- Pratchett

"Any technology distinguishable from magic is insufficiently advanced."
- Benford

"Any magic, sufficiently debased, is indistinguishable from technology."
- Rosenbaum

"Any sufficiently advanced garbage is indistinguishable from magic."
- Sterling

"Any sufficiently advanced technology is indistinguishable from a completely ad-hoc plot device."
- Langford