Knowledge half-life

You are losing your knowledge at 50% every two years, while in every field, knowledge is being doubled every 72 days — Brian Tracy.

You are losing your learned knowledge 50% every two years

This is called “knowledge half-life”. Every two years, your knowledge is 50% lost or forgotten by your brain. If you had 100 units of knowledge, let’s say you memorised 100 formulas or 100 quotes and you didn’t use them, after 2 years, you will remember only 50 of those — with 50% forgotten forever.

In the next 2 year, the remaining 50% knowledge is subjected to another 50% loss. After the end of 4th year, you will only remember 25% of what you originally knew. This should be worrisome because if this is the rate at which you lose your knowledge, even if you remember 100 books by heart, you will end up remembering only 12.5 after 6 years, and 6 books after 8 years losing 94% of what you knew — gone forever.

Should you be worried?

We are living in the age of “knowledge economy”. Knowledge is your “cash” “currency” and “gold” with which you trade everything and create influence in the world. As an individual and Nation, if you are not growing in knowledge, you are growing to become a “mental slave” of somebody else.

How to prevent knowledge loss?

Learning from Brian Tracy (the author of 80+ books and one of the best life trainers out there), you got to spend 1 hour reading every-day just to keep your current level of knowledge intact. Reading 30 minutes would mean your knowledge loss is reduced by 50%, but reading 60 minutes a day would mean you are adding knowledge to yourself at the same rate (speed) as much you are losing.

To prevent knowledge loss, you will have to stir it continuously. Like in making “Kheer”, you stir milk in the pot all the time. Learn, use, transfer, repeat.

Knowledge is doubling every 5–7 years

And while you are losing knowledge, humanity is working to increase the volume of knowledge to double every 5–7 years. Infect in medical science, knowledge is being doubled every 72 days. You heard me right, every two and a half months, the amount of knowledge which existed in the field of medicine is being doubled.

That means if there were one million books on a subject, they will become 2 million within 5–7 years time. Even if you are able to retain your original knowledge year after year, the amount of knowledge which you would know as compared to knowledge out there will be halved in 5–7 years time.

What should you do?

1. Stop memorising knowledge

You must learn to “know” and “understand”. Your memory is not your “reference library” where everything you want should be stored. As you have learned, your brain losses half of its knowledge every 2 years, and that means you cannot keep anything less than essential in it. Our brain stores knowledge in a binary tree, which means the more you memorise, the longer your memory tree gets, and the longer it takes to recall what you knew — and the longer your memory tree is, the likely it is that it will be fudged, party lost or get mixed with other memories to become inaccurate.

Thus train yourself to understand — and once you understand something, you never lose it.

2. Practice what you know

The best way to practice your learned knowledge is to spread it — teach others so you may keep what you know.

3. Add more knowledge rigorously

Studying 1 hour every day is minimal if you want to keep your current knowledge base. Spend 2 hours reading/learning if you actually want to stay in the race with this fast developing world.

4. Don’t worry about what you are losing

If something wasn’t in use, it will be forgotten by default and sometimes it is the best because if you had learned something which wasn’t relevant to your life, it should be forgotten.

Final take aways

• You are losing your memory to half every 2 years.
• To maintain current levels of what you know, study 1 hour everyday and to grow your knowledge study 2 hours everyday.
• Spread what you know, spread the light so you could keep yours on.
• Learning is not a student’s job only. Regardless of what you do, what kind of job/service you offer, learning is an obligation throughout your life. If you are not going up in knowledge, you are going down.

May Allah help you get all you want and all you need.

— Salman Ehsan