In pursuit of their interests, individuals would contribute to market equilibrium. This would happen because, even without the intention of collaborating with other agents, this dynamic would culminate in a positive situation for society as a whole.
This balance would be the result of what we now know as the law of supply and demand.
According to this law, the price of a product is determined by the balance between the number of companies offering the product and the number of consumers looking for it.
The invisible hand is therefore a symbolic representation of the idea that the market itself is organized in the best possible way.