Demand-pull inflation intuition According to the theory, monetary growth increases inflation. 

But how do companies know that there is more money in the economy now than before?
The basic intuition is that the companies either directly know by looking at what the central bank is saying, OR (and more importantly) the money growth means that money is now put into the hands of various agents in the economy. The second case is the important one.

When that money is put into the hands of various people they go out and spend that money. Thus there is increased competition to buy the same amount of goods. (More $$ chasing less goods). That competition to buy means that firms will profit by raising the price, and so they do that when they see the increase in demand.