The lamp is ON. It lights up!

Gate by gate
- NOT B → NOT OFF = ON
- A AND NOT B → ON AND ON = ON
- C OR D → ON OR ON = ON
- (A AND NOT B) OR (C OR D) → ON OR ON = ON
The same circuit in Python
Python has the same three gates built in: and, or and not. ON is True and OFF is False.
A = True
B = False
C = True
D = True
lamp = (A and not B) or (C or D)
print("Is the lamp on?", lamp)
When you run it, it prints:
Is the lamp on? True
Try it: change one of the switches from True to False (or the other way round) and run the code again. Can you find a switch that changes the lamp?