Richard Clark jested:
"I flipped the switch to a light bulb. What direction is the optical
power?"

Seriously, away from and toward are directions. We expect a light bulb
to be an energy source. If it becomes a sink it has a negative effect.

From John E. (Here`s Johnny!) Cinningham`s "The Complete Broadcast
Antenna Handbook", page 243:
"Again, if the base impedance is a negative number, this merely means
that energy is flowing out of a tower (toward the transmitter) instead
of into it (from the transmitter)."

Sign is certainly used to indicate the direction of energy movement or
the same thing, power flow.

Best regards, Richard Harrison, KB5WZI