The fcat that it is a theory should be enough, given that for it to become one it must have passed all tests and criticisms it ever faced with flying colours and be usable in predicting the results of a relevant experiment. If that is not enough, set up an experiment and ask them to choose the variables and conditions for you. You can then use the theory to predict the results and then prove it so.
You would have to lie because you are not a vampire, vampires do not exist.
I would suggest you try to convince them with logical arguments.
they are used to communicate with people
To say 'condensation' in Spanish, you would say 'condensación.'
CONDENSATION
show them a globe, or a picture from space
you will be safe if you always do rightp, but you will get caught, if you are dishonest.
Condensation is the phase change from gas to liquid, so you would be losing energy.
I'm going to wipe the condensation off of the window.
Condensation nuclei are important because they provide surfaces for water vapor to condense on, which leads to the formation of clouds and precipitation. Without condensation nuclei, the process of cloud formation would be much slower and less efficient, impacting the Earth's water cycle and weather patterns.
authoritarian personality theory
Well, without condensation humans life cycle would be all messed up. When condensation occurs, it gathers water as small droplets. So in a way, condensation does help humans