Why Today's Best Business Leaders Look to Stoicism An entrepreneur's guide to this ancient Greek philosophy.

Ask entrepreneurs to name their biggest challenge, and you'll hear plenty of answers: decision-making, prioritizing, staying positive, maintaining momentum. The list goes on. As you may already know, starting and running a business is not for the faint of heart. Now ask those same entrepreneurs whether they have a framework for managing these challenges, and they might have a tougher time answering.

But what if I told you that there's a school of philosophy dating back to ancient Greece that can help you handle all of these obstacles on a daily basis and, as a bonus, may even enrich your quality of life? And better still, you don't have to be a scholar to figure out how to use it. It's called Stoicism, and it's a practical philosophy that's used by some of today's greatest thinkers and business minds, including Tim Ferriss, Ryan Holiday, Arianna Huffington and Jack Dorsey.

Emperor Marcus Aurelius was a big adherent of Stoicism, too, and it helped him to lead Rome for almost two decades. Aurelius wrote about his observations as a Stoic leader in his journals, later published under the title Meditations. Stoicism gave Aurelius a guidebook for living a virtuous life, focusing on what mattered and persevering despite setbacks -- and the Roman emperor had more than a few. But, as he wrote in Meditations, "Our actions may be impeded ... but there can be no impeding our intentions or dispositions."

As entrepreneurs, we can't control every factor that could affect our companies, but we can take a page from the book of Stoicism and control our own actions and reactions. With that in mind, here are some lessons from Stoicism that I've found valuable for running my own company, JotForm, and that I think any entrepreneur will find useful for launching and maintaining a successful business.

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1. How to set your priorities.

"If you seek tranquility, do less. Or (more accurately) do what's essential. Do less, better. Because most of what we do or say is not essential." -- Marcus Aurelius

For a long time, just after I launched my company, I tried to do it all, from customer service to big-picture things like plotting our vision for the business. Unsurprisingly, I wasn't seeing the growth I had hoped for. Time is our most important asset, particularly in the startup world. It's crucial to focus your energy on tasks that move your company forward, what Aurelius called the "essential." Once you start doing that, you're much more likely to hit your larger business goals, be they growing your user base, entering a new market or whatever applies.

For me, doing the essential required automating as much as possible and delegating the rest, i.e. responsibilities such as customer service that were demanding a huge amount of my time but could be completed just as well by someone else on my team.

2. How to curb stress.

Epictetus, a prominent Stoic philosopher in the first and second centuries, wrote that the main goal of Stoicism was "to identify and separate matters so that I can say clearly to myself which are externals, not under my control, and which have to do with the choice I actually control."

Entrepreneurs face various sources of pressure daily: deadlines, competing commitments, investor expectations and customer complaints, to name a few. For some, that pressure turns into stress. And as we all know by now, too much stress is not only bad for our health, it's bad for business in terms of both productivity and profitability.

Others, however, are able to navigate the pressures without becoming overly stressed out. Part of it comes down to recognizing the things you can control, and those you can't, or what Epictetus referred to as the "externals." By focusing on just the "internals," we can save time and promote a more positive work culture.

3. How to stop procrastinating.

"We are not given a short life but we make it short, and we are not ill-supplied but wasteful of it." -- Stoic philosopher Lucius Annaeus Seneca

An important tenet of Stoicism is not wasting time and living every day as though it could be your last. Being constantly mindful of our mortality might sound , well, morbid, but I see it as a positive motivator to live for the present and stop putting things off.

In a letter to his older brother, Seneca described his method for ensuring he was making the most of each day. He'd ask:

How am I better today?

What did I do with my time?

What were my outcomes?

I've found this to be a helpful exercise to incorporate into my daily routine. Knowing that you'll be answering those questions at sthe end of each day is a great way to hold yourself accountable for getting things done.

Related: 5 Reasons Why Philosophy Majors Make Great Entrepreneurs

4. How to manage fear.

To define your company against the competition, you must be innovative. And being innovative requires taking risks -- calculated ones, but risks nonetheless. One might think that the best business people are fearless, but as it turns out, they've simply learned to manage their fears and proceed forward despite them. As any Stoic will tell you, it's useless to wish things in the world were different; rather, we should learn to navigate things as they are, and that includes living with our fears.

To do so, Stoics used a method called "premeditatio malorum" (Latin for the premeditation of evils). Imagine your most dreaded outcome in any situation. Worst case scenario: You're psychologically prepared for whatever the future holds. Best possible scenario: You realize that even the worst outcome won't kill you, and maybe that original fear loses its teeth.

Having your own business is tough. While you can never eliminate the demands -- there will inevitably be pressure and fear and ups and downs -- you can learn to navigate them with a strong, Stoic mentality, and both your wellbeing and your business will be better for it.