So if everybody decides they want to buy tulips and the price of tulips soars- that is because the Central Bank caused them to change their preferences to tulips over other flowers and even over other goods by inflating the money supply.
Did I say that all changes in relative prices are caused by central bank intervention?
No, I said that all central bank interventions cause changes in relative prices.
How exactly do they change preferences?
If you mean during an inflation, it's not that individual's preferences change, it's that the distribution of purchasing power among individuals changes (as I explained).
Suppose the new money ends up going initially to would-be home buyers.
Then home prices get bid up relative other goods/services.
The Fed adds money to the banking system- either by creating it or by purchasing something- like US Treasuries. How does that find its way into tulips and not other goods?
When new money is created, it is not added pro rata to all existing money balances.
If the Fed prints $320 million, we do not each get $1 added to our wallets (if that's what happened, there would be no changes in relative prices).
The money goes first to some group (say, banks), and then another (say, home-builders), and then another (say, employees of home builders), etc, etc.
The new money works its way gradually through the economy, effecting relative prices as it goes (this is called the Cantillon effect).
Why did the price of tulips get into a bubble? Emotions. Everybody decided they wanted one too. They thought if they bought in, they could maybe make some money. It wasn't really about tulips. Then the excitement wore off, folks got tired of tulips (or they got too expensive) and people gave up on them and the prices fell.
If your point is that speculative manias (such as tulipmania) are possible without inflation, well sure they are - so what? That doesn't undermine ABCT. Incidentally, tulipmania occured shortly after the development of central banking in Holland. I'm not terribly familiar with the details of that episode, but I wouldn't be surprised to discover that it was in fact an inflation driven mania.
Did the Fed inflate the money supply prior to the housing bubble (which basically runs from 1999- 2006)?
Yes
M2 is the most commonly used measure of money supply. Was there a big spike in the late 1990's, early 2000's?
Why would there need to be a "big spike"?
Any amount of inflation, whether occuring at a steady rate or accelerating, will cause resource misallocations as I've been describing.
Did they change people's preferences to buy more houses?
See above, it's not about individuals' preferences changing.
Incidentally, the reason that the money ended up in housing in that particular episode (as opposed to, say, tulips) is that yet other government interventions were pushing it in that particular direction (the home loan subsidization programs run through Fannie, Freddie, etc, which were incentivizing banks to make more and more risky home loans [with the new money provided them by the Fed]).