It turns out we can do quite a lot to increase truth, but it's going to take a little effort.
What is Lying? The Stanford Encyclopedia of Philosophy says that there have to be four conditions present to make a lie: a statement about something, the statement be untrue, the statement is told to someone else, and there is an intent to deceive. There are also arguments for and against every one of those conditions in certain situations. If you believe you are telling the truth is it still a lie if your statement later turns out to be false?
50 Ways to Leave a Liar. Here are some (but not all) ways to lie, or at least be untrue.
Lie of Commission. You say the dog is black when you know that dog is white.
Lie of Omission. You're asked if you saw the neighbor's missing dog and you say, "yes" but neglect to mention to that you've decided to keep the dog for yourself.
Lie of Ignorance. You saw the dog at night and really thought it was black but were wrong. Before the invention of a reliable clock that could operate at sea, mariners died by the thousands because the means of determining longitude (e.g., dead reckoning) weren't always correct and their ships were dashed to bits on the rocks. They thought their location was here but it was there instead - although we are missing the "intent to deceive" element presented by Stanford, so perhaps this isn't a lie...it's just not true.
Lie of Looking through the Telescope Backwards. Also called "cherry-picking." The hotly contested 2000 presidential election centered on the results in Florida. After an extensive, multi-year investigation, one person - an Austrian-turned-Canadian - was found to have purposefully cast an illegal vote. But this case and a handful of others out of hundreds of millions of votes cast have created the perceived issue of widespread voter fraud, which in turn has been used to create voter identification laws in many states that have the effect of suppressing voter turnout in certain populations. This sets the stage for....
Lie of Condition. That dress was blue / black or white / gold? The lighting conditions and information presented by a computer screen likely "colored" our judgment, just like our upbringing, current frame of mind, circle of friends, and information sources we are regularly exposed to dictate our preconceived ideas. Which brings us to....
Lie of Perception. Modern forensic evidence has overturned hundreds of criminal convictions, including those based on eyewitness testimony to put someone on death row. A famous experiment presented a video of two sets of people in different shirts passing a basketball back-and-forth for a minute, asking those watching to count the number of times each group caught the ball. Over 50% failed to see a person in a gorilla suit walk across the floor, stop, wave at the camera, and walk off. Really smart people still see just what they want to see. When confronted with the evidence those people that didn't see the gorilla expressed disbelief and sometimes anger - sound like that political discussion a couple of Thanksgiving dinners ago?
The Truth is Out There...Somewhere. So with our faulty perceptions, lack of knowledge, and different grades of liars out there wanting to deceive us for their own gain how can we find truth? It may not be perfectly achievable, but people like asking questions and we LOVE proving someone else wrong, so let's use those things to our advantage. First, check the source - where did this information come from originally, what's their / its reputation, and is there a reason for them to commit some form of lie (e.g., who pays them)? Second, dig into it - if it's a study, what's the sample size, has it been replicated, are the conditions like the one I'm experiencing, can you find counter-evidence, and does it align with previous supported findings? Third, is this a one-off story that is being told many times to conceal a larger, more-relevant truth, like the 1980's "welfare queen" (based on a real person) used to score political points with the aim of cutting basic support for food that millions of people depend on to get by?
Can we still get fooled even if we do everything right? I've done it before and will probably do so again. But if I and lots of people start doing the unglamorous work of applying a few basic principles to what they hear and see the lies will have a harder time gaining traction.