Success in business and in life depends on good decisions, and good decisions depend on two things. One, you need to know the facts. Two, you need to think about them intelligently. 

Most decision-making advice focuses on the second element -- it gives you tips on how to weigh alternatives and frame possibilities in order to think more intelligently about choices. Facts, you might think, basically take care of themselves. You can rely on your eyes and your brain to tell you what you need to know. 

Unfortunately, that's not at all a safe assumption. Perception: How Our Bodies Shape Our Minds, a new book by University of Virginia psychologist Dennis Proffitt and writer Drake Baer, lays out all the ways our brains play tricks on us, warping what we perceive because of our physical state, mood, or circumstances. 

In a recent post digging into the book for UC Berkeley's science center, Jill Suttie lays out a ton of examples, but mind-bending tales of our brains' playing tricks on us abound online. Here are a few to convince you that your brain is lying to you way more than you probably realize. 

1. Things look further away when you're tired. 

Distances are facts, not opinions. There is one objective right answer to the question, "How far away is that?" But if you're short a measuring tape, your brain will make an estimate. And our guesses about distance aren't just affected by sightlines, experience, and other rational factors. Our feelings are also calculated into our estimates. 

"Researchers have found that if you are obese or tired, distances look farther to you," reports Suttie. The reverse is also true -- if you think something is easy to reach, it will seem closer or more accessible than it is in reality. 

"If you are holding something that extends your reach -- like a grabber -- things appear closer to you too," Suttie writes. 

2. Food makes you nicer. 

If you ever need to go before a judge for sentencing, do your utmost to make sure the hearing is scheduled after lunch. Research shows judges are less lenient when they're hungry. They're not the only ones whose perceptions and performance is affected by food. 

"Studies have also found that people who've enjoyed a tall, sugary glass of lemonade tend to be more helpful to others. And children who eat breakfast do better in school and have fewer behavioral problems," notes Suttie. 

"Hangry" is a real thing, and it has significant, real-world impacts on our decision making. 

3. Everything seems harder when you're sad ... 

It's not just hunger that impacts how you see the world; so do other feelings. For instance, "people listening to melancholic music tend to think a hill looks steeper than people listening to happy music," reports Suttie. The world just seems harder when you're sad. 

4. ... and easier when you're with friends. 

The opposite is also true -- good company makes work seem easier. "Anticipating having to carry a heavy load with someone else (as opposed to alone) makes it appear lighter, and just thinking about a friend can make hills seem less steep," adds Suttie. 

5. We guess color from context.  

Remember "The Dress," the explosive internet meme where people couldn't agree whether a dress was white and gold or blue and black? As this fascinating Vox article explains, the disagreement wasn't a freakish one-off occurrence. We're always making inferences about colors based on the situation we see them in. What surrounds a color (or what we assume surrounds a color) can change the shade we see. Just look at this mind-bending example. 

In the case of "The Dress," it's likely that those who "saw" the dress as white and gold assumed they were looking at it in daylight. Those who "saw" black and blue assumed the dress was illuminated by a light bulb. Both groups unconsciously corrected for the lighting, arriving at very different conclusions. 

Beware fast decisions 

Beyond just illustrating exactly how bizarre the human mind can be, these examples offer a cautionary tale for entrepreneurs. It is not safe to assume that you can know facts as basic as the color of an item or the difficulty of a challenge just at a glance. Your mood, body, and context can radically alter your perceptions. 

What seems easy in the morning might look daunting in the afternoon. The perfect color on the designer's desktop might be hideous sitting on a store shelf. All of which should serve as a caution against fast decision making. With brains this wonky, it's best to wait and see if anything looks different the next morning, in different company, or after a snack. 

Being open to new information and our own fallibility has been good advice for ages. It seems even wiser the more we learn about all the ways our brains lie to us.