Why is a capacitor a linear device?
One property for linearity is that the capacitance or some such parameter must not change with voltage or current. Is this enough to make a device linear?
A few sources say that the \$Q=CU\$ has a linear characteristic with voltage and so it is a linear device but wouldn't there be at least one such parameter in a MOSFET/diode that does change with respect to voltage or current in a linear manner - for example the voltage of a diode decreases linearly with the temperature.
So what should I exactly consider for linearity?