Huh?

"In fact, of the seven fundamental metric units — the kilogram, meter, second, ampere, kelvin, mole, and candela — only the kilogram is still dependent on a physical artifact."

Followed by:

"And the luminosity of light, or candela, is measured in terms of power, designated in watts, or joules per second."

I'm not an SI expert, but Wikipedia suggests the candela is in fact an SI base unit with a definition based on physical phenomenon of the universe, so the second sentence seems erroneous.

[edit: clarity]