what changes the form of clouds in the sky into different things when we look at them?

Answer 1

It's a combination of our imagination and our psyche as when we take a Rorshach test. Our imagination feeds our subconscience. My theory.

Answer 2

Well Stormy
There are several factors that play a part in the overall reason for the behavior of clouds
Their water vapor content-----
the prevailing winds (there can be several levels of varying wind speeds and directions at different altitudes playing their own combined parts in this dance)-----
The barometric pressure-----
and--- the temperature (there can be strong variations in the readings of warm and cool at the various altitudes as well with the old---- hot air rising-- cool air falling rule in play big time in this visual production)
So, stormy when you see the magic of the clouds doing their dance for you --- you are witnessing a timeless ritual of nature that has been going on in much the same way for millions of years--- and the visual images that they form for you is their way of telling you just a little touch of what is going on with them and the vital part they play in the world we live in !!!!

Answer 3

And of course from where you look at them and how. Your imagination makes out from the clouds the forms you perceive.