One mom wonders when she can start using logic with her preschooler.


Q. I try to explain to my 3-year-old the reason we have certain rules (like no touching the TV) or why we can't go to the park right now, and he will just throw a tantrum. Other times, he seems to really understand complicated ideas. When can I start using logic with my young child?

A. Between approximately 2 and 3 years, children begin to understand the logical connection between ideas -- the "why" of things -- which is the reason they start to ask "Why?" about almost everything! It is a big milestone in their development and comprehension of how the world works.

What Affects Kids' Understanding

However, this stage can also be very confusing and exasperating for parents. The inconsistency you've described in your son's behavior is a perfect example, reflecting a 3-year-old's still-shaky grasp of logic. One minute he seems very reasonable and wise and the next he acts totally irrational. This is coupled with the fact that 3-year-olds are still working hard on managing their emotions, which are strong at this stage and can interfere with, and often trump, their ability to act as rational beings.

Other factors will also influence how your child accepts and responds to your logical explanations. Is he tired or hungry? Is he anticipating something? Is he a temperamentally intense, persistent kid? These variables can strain his ability to act (and think) like a "big boy."

So when you tell your son he can't have cake for lunch because his body needs healthy foods to grow strong, he may quickly comply. But when you tell him he can't go to the playground before bed, he might completely lose it. You're left confused -- why is one explanation harder to understand than the other? The answer is: It's not. That's just how a 3-year-old processes the world.

The Bottom Line

At this point it is best to explain the rule matter-of-factly and to be consistent in the follow-through. If your son throws a tantrum, validate his unhappiness, anger, or frustration but don't relent as this will just make the tantrum a successful tool for him. It will also confuse him about what the rules really are. When your actions match your words, he will learn the rules much more quickly.

Just wait for the deja vu you'll feel in 12 years when you try to explain curfews. Until then, enjoy your passionate 3-year-old and rest assured that understanding logical connections and family rules is a skill he will gradually sharpen over the next few years.

Claire Lerner, LCSW, is a child development specialist at Zero to Three, a national nonprofit promoting the healthy development of babies and toddlers (

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