"I'm a total fraud. When will everyone figure me out?” I thought to myself as I sat negotiating a contract with my client, who held many more degrees than I and was many decades my senior. After years of competent work and expertise in the space, I couldn't shake this feeling that it was all a flimsy house of cards.

That, dear readers, is textbook ”impostor syndrome,” where you don't believe your accomplishments to be a result of your own achievements. I've discussed it with other executives, professors and professionals and found it's actually exceedingly common – we all carry around this nagging feeling. Though it still creeps up on me again now and then, naming it has helped cure it.

To help you dispel some of your worries and insecurities, I'd like to touch on five of the many concepts I’ve borrowed from different disciplines that continue to help make me a more confident leader, decision maker and person.

1. Maslow's Hierarchy: A psychological concept that stacks an individual’s needs neatly into a pyramid, highlighting the idea that only when an individual is satiated at one level can he or she feel confident to move to the next. Maslow claimed that everyone starts with physiological needs like food and water and moves upwards towards inevitable self-actualization. It reminds us how small and frail we are as human beings, but also how great we can become.

2. Cognitive Bias: We all carry tendencies to think in particular ways, even when attempting to be scientific and particularly when trying to shortcut decision making, which can often skew rational thinking and good judgment. I encourage you to research various  types of bias – there are hundreds –  like clustering illusion, where you see larger patterns based on small samples of data (I describe this briefly in my last article). Or hindsight bias, where you see past events as predictive of future performance. Being aware of bias can change the way you think about the way you think.

3. Risk/Reward Ratio: Entrepreneurs by definition are risk takers, but I like to think that a great founder is a master of calculating risk and taking action at the boundary conditions. It’s crucial when contemplating any risk to weigh it directly against the gain or reward you could glean from it just as an investor would. If the risks outweigh any rewards you could imagine, particularly in the long term, it is not worth pursuing that venture (also see opportunity cost). Looking at opportunities on a balanced scale of risk and reward can take emotion out of the decision.

4. Pareto's Principle: The 80/20 rule (mentioned in my previous article) is indispensable when thinking about how I spend my time, which clients we sign and/or renew and how we build products. It states that only 20% of the inputs lead to 80% of the outputs: 80% of your revenue comes from 20% of your clients; 80% of your productivity comes from 20% of your working time; 80% of your sales comes from 20% of your products. To me, this was so liberating! Part ways with clients who are not partners. Use time wisely and expect the same from your staff, but understand that productivity is not always linear nor perfect. Recognizing this gives you license to say, “Fast, good, or cheap – pick two,” a common phrase in software development.

5. Correlation and Causation: Just because two things are related does not mean that one caused the other. This is really helpful in gut checking your conclusions. If an online marketing strategy isn't working, don’t jump to blame the technology you've deployed. Perhaps the real culprit is the effectiveness of the marketing message. If web traffic has suddenly taken off, don't assume that it was because of the email you just sent. Lots of variables, both internal and external to your company, cause things to happen. Take a look at the more holistic picture and the solid data behind it. Don't assume causation; build a case and prove it.

Learning concepts from other industries can make you a more worldly person and change the way you think about yourself and your environment. In my case it reminded me that I'm the real deal. I encourage you to cross-pollinate. Pick up a physics or philosophy book to widen your perspective and bring fresh concepts into your industry. Tell me about some concepts that have helped you on your journey on twitter at @daynasessa.