Decide by rules, not feelings

Think of your mother making her famous rava dosa. She does not guess. She has a rule she follows every single time: so many spoons of rava, so much water, rest the batter, pour it thin, wait for the edges to turn golden. Because she follows the same steps, the dosa comes out right whether she is happy, tired, or in a hurry. The recipe protects her from her own mood.

Now think of a boy named Arjun who cooks by feeling. Some days he adds extra salt because he feels like it. Some days he flips the dosa too early because he is excited. His dosa is different every time - sometimes good, mostly not - because his feelings are steering the pan.

Deepak Shenoy, an Indian investor and writer who explains money in plain words, teaches something very close to this about the share market. He says the best way to invest is to write down clear rules beforehand - what you will buy, how much, when you will sell - and then follow those rules exactly, like a recipe, even when you do not feel like it. The whole point is to keep your feelings and other people's "hot tips" out of the driver's seat. This study is about why a written rule beats a moody guess, almost every time.

A rule here just means a decision you write down before the money is on the line, in a calm moment, so that later - when you are scared or greedy - you do not have to decide again. You just do what the rule says. A feeling, by contrast, changes minute to minute. It rises when prices rise and falls when prices fall. That is exactly the wrong time to be making choices.

Here is why the rule wins. Feelings are strongest at the worst moments. When a share is crashing and everyone is scared, your feeling screams "sell now, save yourself!" - and that is usually the moment you should hold or even buy. When a share is shooting up and everyone is happy, your feeling shouts "buy more, don't miss out!" - and that is often the moment to be careful. The feeling always arrives pointing the wrong way. A rule written in a calm moment does not have this problem, because it was decided when nobody was scared or greedy.

A rule also has another quiet gift: it lets you check yourself later. If you followed a written rule and it went wrong, you can look back, see exactly what the rule said, and improve it. But if you acted on a feeling, there is nothing to check - "I just felt like it" teaches you nothing. Think of a fair cricket umpire. The umpire follows written rules of the game. Even if the crowd is screaming, the umpire gives the same decision the rulebook demands. That is what makes the umpire trusted. Shenoy wants you to be your own fair umpire - following your written rules, ignoring the screaming crowd.

illustrative Kabir and Priya are cousins. Each has ₹1,00,000 to invest. In a calm month, Priya writes a simple rule for herself: "I will put ₹10,000 into my chosen basket on the 1st of every month, no matter what the price is, and I will not sell for five years." Kabir writes nothing. He decides he will "buy when it feels right and sell when it feels risky."

Then the market falls hard - down about 30% over a few months. Watch the feeling do its damage. Kabir, seeing red everywhere and scared of losing more, stops buying and even sells near the bottom to "feel safe." Priya, following her rule like a recipe, keeps buying her ₹10,000 every month - which means she is quietly buying more units while prices are low, because each ₹10,000 now buys cheaper.

A year later the market recovers. Priya, who kept buying low, is comfortably ahead. Kabir, who sold at the bottom and bought back only after prices had risen again, is behind - even though both cousins started with the same money and the same market. Nothing separated them except this: Priya let a calm rule decide, and Kabir let a scared feeling decide. The market was the same for both. Their behaviour was the whole difference.

A rule is only as good as the thinking behind it. Following a bad rule faithfully is still bad. If your rule is "buy whatever share my neighbour is excited about," obeying it strictly will not save you. The value of rules comes from writing sensible ones in a calm mind - not from blind obedience to any rule at all. So the skill is two parts: think carefully first, then follow faithfully.

No rule fits every situation forever. The world changes. A rule that made sense years ago might need updating as your life, your goals, or the facts change. The danger is treating an old rule as sacred and never reviewing it. The fix is gentle: review your rules on a calm, fixed schedule - not in a panic, but not never either.

Following a rule is harder than writing one. It is easy to write "I will not sell in a crash." It is very hard to actually sit still while your money seems to be shrinking and everyone around you is selling. Knowing the rule does not switch off the fear. That is why writing it down, telling someone, and keeping it simple all help - they make it a little harder for the feeling to talk you out of it.

This idea needs no special tools and fits India perfectly. Our markets are full of loud voices - WhatsApp groups, TV shouting, a cousin's "sure-shot tip," a YouTube channel promising to double your money. Each of these is designed to poke your feelings and make you act right now. A written rule is your shield against all of them. When a tip arrives, your rule already has an answer: "This is not in my plan, so I do nothing." That single sentence has saved more Indian savers than any clever trick.

But remember what a rule cannot do. It cannot tell you which specific company will do well - nothing can promise that. It cannot remove risk; the market can still fall. And it cannot decide for you what your goals are - that part is yours. A rule is a way to behave steadily toward goals you have already chosen calmly. It keeps your hands steady; it does not see the future. Used that way - as steadiness, not as a crystal ball - it is one of the most useful habits an ordinary Indian saver can build.

• Write the rule in a calm moment. Decide what, how much, and for how long before any money is at stake - the calm you is wiser than the scared you.
• Make the rule simple enough to actually follow. A rule you can say in one breath beats a clever rule you abandon under pressure.
• When a tip or scary headline arrives, ask "what does my rule say?" If it is not in your plan, doing nothing is a full answer.
• Notice when a feeling is loudest. Strong fear or strong greed is a signal to slow down and re-read your rule, not to act.
• Review rules on a fixed schedule, not in a panic. Update them calmly as your life changes - never in the middle of a crash or a boom.
• Keep a record. Write why you made each rule, so you can check and improve it later instead of guessing.