How do you know that scientists are telling the truth?

Answer 1

You can't always know when someone is telling the truth - however you can get a good grasp of how plausible what they say is by seeing how credible they are. For instance, someone from a non-existent background or dubious looking education may not be as trust worthy as someone who is, say, from a Cambridge/Oxford education and has produced many papers on the same subject. Science itself lends itself to truth, as nothing is accepted unless it has been thoroughly tested in practise. Without evidence, anything a scientist might say is worth zero. Unless of course they're a theoretical scientist, in which case it is based around other known truths! Generally, a scientist will do what they do because they have a passion for it. So, it is not in their best interests to falsify what they say, as it could damage their reputation as a scientist, and then their ability to perform further examinations. Ultimately, it is up to the individual to decide what they believe or disbelieve.