Irreversibility refers to the preoperational childs tendency to

Your baby’s big enough to say “More!” when they want more cereal. They’re even able to follow simple instructions and throw their used napkin in the garbage. Yup, they’ve moved onto a new stage of development.

According to Swiss psychologist Jean Piaget, there are four stages of cognitive development (thinking and reasoning) that we move through as we grow into adults. The delightful stage your child has entered, the second stage, is called the preoperational stage.

The name of this stage hints to what’s happening here: “Operational” refers to the ability to manipulate information logically. Yes, your child is thinking. But they can’t yet use logic to transform, combine, or separate ideas.

So they’re “pre” operational. They’re learning about the world by experiencing it, but they’re not yet able to manipulate the information that they’ve learned.

This stage lasts from around age 2 until about age 7.

Your toddler hits the preoperational stage between 18 to 24 months when they start to talk. As they build up their experiences of the world around them, they move towards the stage where they can use logical thought and imagine things. By the time your child is about 7 years old, they can use their imagination and play make-believe.

Your charming toddler is growing up. Want to put a name to what you’re seeing? Here’s a list of the main characteristics of this stage of development.

Egocentrism

You’ve probably noticed that your child thinks of one thing: themselves. That’s perfectly normal for this developmental stage. They want that drink NOW — not after you’ve finished throwing the laundry into the dryer.

Egocentrism also means that your child assumes that you see, hear, and feel the same things they do. But hang in there, because by the time they hit 4 years old (give or take), they’ll be able to understand something from your point of view.

Centration

This is the tendency to focus on only one aspect of a situation at a time. Try lining up two rows of paper clips in such a way that a row of five paper clips is longer than a row of seven paper clips. Ask your young child to point to the row that has more paper clips and she’ll point to the row of five.

This is because they’re focusing on one aspect only (length) and can’t manipulate two (length and number). As your little one grows, they’ll develop the ability to decenter.

Conservation

Conservation is related to centration. It’s the understanding that a quantity stays the same even if you change the size, shape, or container it’s in. Piaget found that most children can’t understand this concept before 5 years old.

Curious? Try it out yourself. Pour equal amounts of juice into two identical disposable cups. Then pour one cup into a tall, thin cup and ask your child to choose the cup that contains more. Chances are, they’ll point to the tall, thin cup.

Parallel play

At the beginning of this stage you’ll notice that your child plays alongside other children but not with them. Don’t worry — this doesn’t mean your little one is antisocial by any means! They’re simply absorbed in their own world.

Although your kiddo may be talking, they’re using their speech to express what they see, feel, and need. They don’t yet realize that speech is the tool to becoming social.

Symbolic representation

During the early preoperational period, between 2 and 3 years old, your child will begin to realize that words and objects are symbols for something else. Watch how excited they become when they say “Mommy” and see you melting.

Let’s pretend

As your child develops within this stage, they’ll move from parallel playing to including other children in games. That’s when “let’s pretend” games happen.

According to Piaget, children’s pretend play helps them solidify the concepts that they’re developing cognitively. Here’s when your dining room chairs become a bus. Keep an eye out: You may need to referee when your child and their playmate fight over who’s the driver and who’s the passenger.

Artificialism

Piaget defined this as the assumption that everything that exists had to have been made by a sentient being, such as God or a human. This being is responsible for its qualities and movements. In other words, in the eyes of your child, rain isn’t a natural phenomenon — someone is making it rain.

Irreversibility

This is a stage where your child can’t imagine that a sequence of events can be reversed to their starting point.

As your child moves from the sensorimotor stage (the first of Piaget’s cognitive development stages) to the preoperational stage, you’ll notice their imagination developing.

When they zoom around the room with their arms outstretched because they’re an airplane, keep out of the way! If your little one bursts into tears because their playmate has lured away their imaginative puppy, you’ll have to try and sympathize with their pain.

Role-playing is also a thing at this stage — your kiddo may pretend to be “daddy,” “mommy,” “teacher,” or “doctor,” to name a few.

Your head is spinning with deadlines, shopping lists, and doctor’s appointments. Can you really afford to take a few moments to just play? Here are some quick and easy activities you can enjoy together.

• Role play can help your child overcome egocentrism because this is a way to put themselves in someone else’s shoes. Keep a box of costume items handy (old scarves, hats, purses, aprons) so that your little one can dress up and pretend to be someone else.
• Let your child play with materials that change shape so that they can begin to understand conservation. A ball of play dough can be squashed into a flat shape that seems bigger, but is it? In the bath tub, have them pour water into different shaped cups and bottles.
• Have more time? Set up a corner in your house to look like the doctor’s office you just visited. Acting out what she experienced will help your child to internalize what they learned.
• Hands-on practice will help your child develop symbolic representation. Have them roll playdough into the shapes of letters or use stickers to fill in the shapes of letters. Use letter-shaped magnets to build words on your refrigerator door.
• Don’t stop with the tactile. Play smell and taste games: Blindfold your child and encourage them to guess what something is based on its smell or taste.

Don’t panic if you think your child isn’t sticking to this timeline. It’s perfectly normal for children to pass through the stages at different ages than these averages.

It’s also perfectly normal to move on to the next stage and still hold on to the characteristics of the previous stage. No one-size-fits-all applies here. When this stage gets challenging, remember that this little person will grow up to be an amazing adult!