How to Stop Negative Thoughts & Think Clearly

Hey,

Does your mind ever torture you with negative thoughts?

Has my girlfriend cheated on me?
Will I ever succeed?
Maybe I’m a narcissist.

My mind sometimes runs wild. And it kills my mood and sleep.

I’ve been practicing Stoicism for 3 years now, but..

I never thought Stoicism could stop bad thoughts.

Turns out, it can’t.

You see, thoughts are impulsive.

You can choose what to think.

But,

Most of the time, your mind throws you whatever the subconscious is working on at that time.

Stoicism, although 2,000 years old, knew that.

They said that propathé—automatic emotions like negative surprise when someone scares you—come from automatic thoughts.

So they are not under your control.

What’s under your control, though, is not believing these negative thoughts.

They thought it was so important that Epictetus’s educational system was based on what to believe (what is true) and what not to believe (what is false).

He said that if you fail to do that, you give rise to negative emotions—passions—that manipulate you like a puppet.

(We talked about that in a previous email.)

Mastering these thoughts leads to thinking clearly.

And that’s why I’ll give you the exact framework the Stoics used:

How to Think Clearly
A short Stoic course on managing impressions

You don’t suffer from reality. You suffer from your interpretation of it.
A text, a glance, a tone. None of these hurt you.
It’s the meaning you attach that does.

That meaning begins with what the Stoics called an impression (phantasia):

The mental picture that hits you when something happens.

You see a frown → the impression strikes: He’s angry with me.

You feel your phone buzz → Something’s wrong.

Impressions (thoughts) come uninvited.

They’re automatic, fast, and emotional.

Then comes the critical moment:

Assent.

That’s when your reason decides whether to believe the impression or withhold judgment.

Epictetus called this your faculty of assent—the inner governor that separates a free mind from a reactive one.

Assent is not passive acceptance. It’s a conscious “yes” to a thought.

And every “yes” creates your beliefs, your emotions, and your world.

False assent → false belief → wrong action → turmoil.
Careful assent → true belief → right action → peace.

Freedom, the Stoics said, isn’t doing whatever you want. It’s being able to choose your response.

They can chain your body, but not your judgment.

Practice:
When an impression hits, say, “Wait for me a little. Let me see what you are and what you really represent.”

Epictetus laid down 3 questions to understand whether to agree or disagree with an impression.

Ask:

1. Is this from what is, or just what I imagine?

2. Does it match what really is?

3. Could it possibly be false?

If not certain, suspend.
If certain—assent and act.

Here are 3 modern-day examples:

1. Social Media Comparison
You scroll Instagram.

You see a friend on vacation, smiling, drink in hand.

Impression: “They’re happier than me. I’m falling behind.”

You assent—and feel envy, frustration, and self-doubt.

Withholding assent: “This is an image, not reality. I don’t know how they feel. My worth isn’t measured by photos anyway.”

The impression loses its power. Peace returns.

2. Work and Rejection
You send an email pitch.

Hours pass—no reply.

Impression: “They ignored me. My work must not be good enough.”

You assent—and spiral into self-criticism.

Withholding assent: “All I know is they haven’t replied yet. Maybe they’re busy. The silence says nothing about my value.”

The mind stays calm. You conserve energy for action instead of worry.

3. Relationship Anxiety
Your partner says, “We need to talk.”

Impression: “Something’s wrong. They’re upset with me.”

You assent—fear tightens your chest, imagination takes over.

Withholding assent: “All I know is they want to talk. Meaning unknown. I’ll wait and listen.”

You stay steady. And wait to find out.

Always remember to pause before agreeing with a thought.

The goal as aspiring Stoics is to think clearly.

Because thinking clearly means better probabilities of making good decisions.

Good decisions mean wise decisions.

Wise decisions mean virtue.

And acting with virtue means a happy, well-lived life.

See you next week, friend, for the next topic!
Ioannis Sintoris or Said the Stoic

PS. My book contains a full, detailed guide to how to master the art of thinking clearly for the modern reader.

Practice the virtue of patience till it gets out.

And then you can read it.