Never buy lies.
Get the truth and never sell it; also get wisdom, discipline, and good judgment.
The older I get the harder this seems to be. There are many lies floating around in this world and we tend to get invested in them. We invest our money, time, energy, emotions, prayers and relationships into dumb ideas and when they turn out false it seems easier to just press on. This can especially be the case when you are part of a large organization, family, or peer group that has bought into something foolish. The crowd has a way of convincing the best of us to ignore the truth.
Herd mentality can be insidious.